Codeforces : From Newbie to Expert (800-Rated)

 Let's do it ... I will be sharing all solutions here (recent solutions at the top, or find by ctrl+f)

                                


Important Link : ProblemSet

Video Explanations : Check Here



100. Magical Sticks

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int t; cin>>t;
  6. while(t--){
  7. int n; cin>>n;
  8. cout<<(n+1)/2<<endl;
  9. }
  10. }



99. Spell Check

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int t, n; cin>>t;
  5. string s;
  6. while(t--){
  7. cin>>n>>s;
  8. sort(s.begin(), s.end());
  9. cout<<(s=="Timru"?"YES":"NO")<<endl;
  10. }
  11. }



98. Floor Number

  1. #include<bits/stdc++.h>
  2. using namespace std;
  6. int main()
  7. {
  8. long long t,n,x;
  9. cin>>t;
  10. while(t--){
  11. int n,x; cin>>n>>x;
  13. if(n<=2) cout<<1<<endl;
  14. else{
  15. if((n-2)%x==0) cout<<(n-2)/x + 1<<endl;
  16. else cout<<(n-2)/x + 2<<endl;
  17. }
  19. }
  20. }



97. To My Critics

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int t, a, b, c;
  6. cin >> t;
  7. while(t--){
  8. cin >> a >> b >> c;
  9. if(a + b >= 10 || a + c >= 10 || b + c >= 10)
  10. cout << "YES\n";
  11. else
  12. cout << "NO\n";
  13. }
  14. return 0;
  15. }



96. Minutes Before the New Year

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int t; cin>>t;
  6. while(t--){
  7. int h,m; cin>>h>>m;
  8. cout<<(24-h)*60 - m<<endl;
  9. }
  10. }



95. Brain's Photos

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int n,m; cin>>n>>m;
  6. char c;
  7. while(cin>>c){
  8. if(c!='B' && c!='W' && c!='G'){
  9. cout<<"#Color";
  10. return 0;
  11. }
  12. }
  13. cout<<"#Black&White";
  14. }



94. Vanya and Cubes

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int n,h = 0,cnt=0;
  6. cin>>n;
  7. while(cnt<=n){
  8. h++;
  9. cnt+= h*(h+1)/2;
  10. }
  11. cout<<h-1;
  12. }



93. Fair Playoff

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int t; cin>>t;
  6. while(t--){
  7. int s1,s2,s3,s4;
  8. cin>>s1>>s2>>s3>>s4;
  9. if(min(s1,s2)>max(s3,s4) || min(s3,s4)>max(s1,s2))
  10. cout<<"NO"<<endl;
  11. else cout<<"YES"<<endl;
  12. }
  13. }



92. Honest Coach

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int t; cin>>t;
  6. while(t--){
  7. int n, x=INT_MAX;
  8. cin>>n;
  9. int a[n];
  10. for(int i=0; i<n; i++)
  11. cin>>a[i];
  12. sort(a,a+n);
  13. for(int i=1; i<n; i++)
  14. x = min(x,a[i]-a[i-1]);
  15. cout<<x<<endl;
  16. }
  17. }



91. Bachgold Problem 

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int n; cin>>n;
  6. cout<<n/2<<endl;
  7. for(int i=1; i<n/2; i++)
  8. cout<<2<<" ";
  9. cout<<n%2+2;
  10. }




90. Fair Division

  1. #include <bits/stdc++.h>
  2. using namespace std;
  3.  
  4. void solve(){
  6. int n, i, sum = 0, cnt1 = 0;
  7. cin>>n;
  9. while(n--){
  10. cin>>i;
  11. sum += i; cnt1 += (i==1);
  12. }
  13.  
  14. if(sum%2 == 0) {
  16. if( sum%4 == 0 || (sum/2%2 == 1 && cnt1 > 1))
  17. cout<<"YES\n";
  19. else cout<<"NO\n";
  20. }
  22. else cout<<"NO\n";
  23.  
  24. }
  25.  

  27. int main(){
  28. int t; cin>>t;
  29. while(t--){
  30. solve();
  31. }
  32. }



89. Square String?

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int t; cin>>t;
  5. while(t--){
  6. string S,s; cin>>S;
  7. s = S.substr(0,S.size()/2);
  8. if(s+s==S) cout<<"YES\n";
  9. else cout<<"NO\n";
  10. }
  11. }



88. Panoramix's Prediction

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. bool isprime(int n){
  5. for(int i=2; i*i<=n; i++)
  6. if(n%i==0) return false; //no prime
  7. return true; //yes prime
  8. }
  9.  
  10. int main(){
  11. int n,m,i; cin>>n>>m;
  12. for(i=n+1; i<=m; i++){
  13. if(isprime(i)) break;
  14. }
  15. cout<<(i==m? "YES":"NO");
  16. }



87. Polycarp and Coins

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int t; cin>>t;
  5. while(t--){
  6. int n; cin>>n;
  7. cout<<n/3 + (n%3==1)<<" "<<n/3+(n%3==2)<<endl;
  8. }
  9. }


86. Two Arrays And Swaps

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int t; cin>>t;
  5. while(t--){
  6. int n,k;
  7. cin>>n>>k;
  8. int a[n], b[n];
  9. for(int i=0; i<n; i++) cin>>a[i];
  10. for(int i=0; i<n; i++) cin>>b[i];
  11. while(k--){
  12. sort(a,a+n);
  13. sort(b,b+n);
  14. if(b[n-1]>a[0])
  15. swap(a[0],b[n-1]);
  16. }
  18. int sum=0;
  19. for(int i=0; i<n; i++) sum+=a[i];
  20. cout<<sum<<'\n';
  21.  
  22. }
  23. }



85. Maximum GCD

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int t,n; cin>>t;
  5. while(t--){
  6. cin>>n; cout<<n/2<<endl;
  7. }
  8. }



84. Minimal Square

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int t; cin>>t;
  5. while(t--){
  6. int a,b; cin>>a>>b;
  7. int side = max(2*min(a,b), max(a,b));
  8. cout<<side*side<<endl;
  9. }
  10. }



83. Boring Apartments

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int t; cin>>t;
  5. while(t--){
  6. string s; cin>>s;
  7. cout<< (s[0]-'1')*10 + s.size()*(s.size()+1)/2<<endl;
  8. }
  9. }



82. Plus or Minus

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int t; cin>>t;
  5. while(t--){
  6. int a,b,c; cin>>a>>b>>c;
  7. cout<<(a<c?'+':'-')<<endl;
  8. }
  9. }



81. Plus One on the Subset

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int t; cin>>t;
  5. while(t--){
  6. int n; cin>>n;
  7. int a[n];
  8. for(int i=0; i<n; i++) cin>>a[i];
  9. sort(a,a+n);
  10. cout<<a[n-1]-a[0]<<endl;
  11. }
  12. }



80. Medium Number

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int t; cin>>t;
  5. while(t--){
  6. int v[3];
  7. cin>>v[0]>>v[1]>>v[2];
  8. sort(v,v+3);
  9. cout<<v[1]<<endl;
  10. }
  11. }



79. Do Not Be Distracted!

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int n, t; cin>>t;
  6. while(t--){
  7. cin>>n;
  8. map<char,int> m;
  9. string s; cin>>s;
  10. int flag = 1;
  11. m[s[0]] = 1;
  12. for(int i=1; i<n; i++){
  13. if(m[s[i]]==1 && s[i]!=s[i-1]){
  14. flag=0;
  15. break;
  16. }
  17. m[s[i]] = 1;
  19. }
  20. cout<<(flag?"YES":"NO")<<endl;
  21. }
  22. }



78. Codeforces Checking

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int t; cin>>t;
  5. string s="codeforces";
  6. while(t--){
  7. char c; cin>>c;
  8. cout<<(s.find(c)==-1?"NO\n":"YES\n");
  9. }
  10. }



77. Even Array

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int t; cin>>t;
  6. while(t--){
  7. int n; cin>>n;
  8. int a[n]; vector<int> cnt{0,0};
  9.  
  10. for(int i=0; i<n; i++){
  11. cin>>a[i];
  12. if(a[i]%2 != i%2) cnt[i%2]++;
  13. }
  14.  
  15. if(cnt[0] != cnt[1]) cout<<-1<<endl;
  16. else cout<<cnt[0]<<endl;
  17. }
  18.  
  19. }
  20.  
  21. // we could also write like this vector<int> ct(2, 0);
  22. // in C++ creates a vector named cnt containing two elements,
  23. // both initialized to the value 0



76. Black Square

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int a[5],c=0; //calories
  5. string s;
  6.  
  7. int main(){
  8. cin>>a[1]>>a[2]>>a[3]>>a[4]>>s;
  9. for(int i=0; i<s.size(); i++){
  10. c += a[s[i]-'0'];
  11. }
  12. cout<<c;
  13. }



75. Die Roll

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int y,w,d; cin>>y>>w;
  5. d = 6 - max(y,w) + 1;
  6. cout<<d/__gcd(d,6)<<'/'<<6/__gcd(d,6);
  7. }



74. Required Remainder

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int t; cin>>t;
  5. while(t--){
  6. int x,y,n;
  7. cin>>x>>y>>n;
  8. cout<<((n-y)/x)*x+y<<endl;
  9. }
  10. }


73. Division?

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int t; cin>>t;
  5. while(t--){
  6. int r; cin>>r;
  7. cout<<"Division ";
  8. if(r>=1900) cout<<1<<endl;
  9. else if(r>=1600) cout<<2<<endl;
  10. else if(r>=1400) cout<<3<<endl;
  11. else cout<<4<<endl;
  12. }
  13. }



72. Lucky?

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int t; cin>>t;
  5. while(t--){
  6. string s; cin>>s;
  7. cout<<(s[0]+s[1]+s[2] == s[3]+s[4]+s[5]?"YES" : "NO")<<'\n';
  8. }
  9. }



71. Mishka and Game

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int n, p=0; cin>>n;
  6. while(n--){
  7. int m,c;
  8. cin>>m>>c;
  9. p += (m > c); //+ve points
  10. p -= (m < c);
  11. }
  13. if(p>0) cout<<"Mishka"<<endl;
  14. else if(p<0) cout<<"Chris"<<endl;
  15. else cout<<"Friendship is magic!^^"<<endl;
  16. }



70. Balanced Array

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int t; cin>>t;
  5. while(t--){
  6. int n; cin>>n;
  7. if((n/2)%2 != 0) cout<<"No\n";
  8. else{
  9. cout<<"YES\n";
  10. for(int i=1; i<=n/2; i++)
  11. cout<< i*2 << ' ';
  12. for(int i=1; i<n/2; i++)
  13. cout<< (i*2) - 1 << ' ';
  14. cout<< n + (n/2 - 1) <<'\n';
  15. }
  16. }
  17. }



69. Dislike of Threes

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  6. int t,n; cin>>t;
  7.  
  8. while(t--){
  9.  
  10. cin>>n;
  11.  
  12. for(int i=1; i<=n; i++){
  13. if(i%3==0 || i%10==3) n++;
  14. }
  15.  
  16. cout<<n<<'\n';
  17. }
  18.  
  19. }



68. Short Substrings

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int t; cin>>t;
  5. while(t--){
  6. string s; cin>>s;
  7. for(int i=0; i<s.size(); i+=2){
  8. cout<<s[i];
  9. }
  10. cout<<s.back()<<'\n';
  11. }
  12. }



67. Marathon

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int t,a,b,c,d;
  5. cin>>t;
  6. while(t--){
  7. cin>>a>>b>>c>>d;
  8. cout<<(b>a)+(c>a)+(d>a)<<endl;
  9. }
  10. return 0;
  11. }



66. Team Olympiad

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. vector<int> in[4];
  4. int c[4];
  5. int main(){
  6. int n, t, w;
  7. cin>>n;
  9. for(int i=1; i<=n; i++){
  10. cin>>t;
  11. in[t].push_back(i);
  12. c[t]++;
  13. }
  15. w = min(c[1],min(c[2],c[3]));
  16. cout<<w<<endl;
  17.  
  18. for(int i=0; i<w; i++){
  19. cout<<in[1][i]<<" "<<in[2][i]<<" "<<in[3][i]<<endl;
  20. }
  21. }
  22.  
  23. // Input : 7
  24. // 1 3 1 3 2 1 2
  26. // Progress :
  27. // in[1]: 1,3,6 c[1]: 3
  28. // in[3]: 2,4 c[3]: 2
  29. // in[2]: 5,7 c[2]: 2
  31. // Output : 2
  32. // 1 5 2
  33. // 3 7 4




65. Holiday Of Equality

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int a[101],n,sum=0; cin>>n;
  5. for(int i=0; i<n; i++) cin>>a[i];
  6. sort(a,a+n);
  7. for(int i=0; i<n; i++) sum+=a[n-1]-a[i];
  8. cout<<sum;
  9. }


64. Borze

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. char c;
  5. while(cin>>c){
  6. if(c=='.') cout<<0;
  7. else{
  8. cin>>c;
  9. if(c=='.') cout<<1;
  10. else cout<<2;
  11. }
  12. }
  14. }



63. Choosing Teams

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int n,k,cnt=0,y;
  5. cin>>n>>k;
  6. while(n--){
  7. cin>>y;
  8. if(y<=5-k) cnt++;
  9. }
  10. cout<<cnt/3;
  11. }


62. Design Tutorial: Learn from Math

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int n; cin>>n;
  5. if(n%2==0) cout<<4<<" "<<n-4;
  6. else cout<<9<<" "<<n-9;
  7. }



61. YES or YES?

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int t; cin>>t;
  5. while(t--){
  6. char s[4]; cin>>s;
  7. if(strcmpi(s,"yes")==0) cout<<"YES"<<endl;
  8. else cout<<"NO"<<endl;
  9. }
  10. }


60. Sereja and Dima

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int a[1000], b[2];
  4. int main(){
  5. int n;
  6. cin>>n;
  7. int l=0, r=n-1;
  8. for(int i=0; i<n; i++) cin>>a[i];
  9. for(int i=0; i<n; i++)
  10. if(a[l] > a[r]) {
  11. b[i%2]+=a[l];
  12. l++;
  13. }
  14. else {
  15. b[i%2]+=a[r];
  16. r--;
  17. }
  18. cout<<b[0]<<" "<<b[1];
  20. }



59. Spy Detected!

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int t; cin>>t;
  5. while(t--){
  6. int n; cin>>n;
  7. int a[n],cnt[101]={0};
  8. for(int i=1; i<=n; i++){
  9. cin>>a[i];
  10. cnt[a[i]]++;
  11. }
  12. for(int i=1; i<=n; i++){
  13. if(cnt[a[i]]==1)
  14. cout<<i<<"\n";
  15. }
  16. }
  17.  
  18. }



58. Sum

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int a,b,c,t; cin>>t;
  5. while(t--){
  6. cin>>a>>b>>c;
  7. if(a+b==c|| b+c==a || c+a==b)
  8. cout<<"YES"<<'\n';
  9. else cout<<"NO"<<'\n';
  10. }
  11. }



57. Again Twenty Five!

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. cout<<25;
  5. }



56. Yet Another Two Integers Problem

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int t,a,b;
  5. cin>>t;
  6. while(t--){
  7. cin>>a>>b;
  8. int d = abs(a-b);
  9. if(d%10==0) cout<<d/10<<endl;
  10. else cout<<d/10+1<<endl;
  11. }
  12. }



55. Soft Drinking

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int n,k,l,c,d,p,nl,np;
  5. cin>>n>>k>>l>>c>>d>>p>>nl>>np;
  6. cout<<min(k*l/nl,min(c*d,p/np))/n;
  7. return 0;
  8. }



54. Remove Smallest

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int t; cin>>t;
  5. while(t--){
  6. int n, flag=0; cin>>n;
  7. int a[n];
  8. for(int i=0; i<n; i++){
  9. cin>>a[i];
  10. }
  11. sort(a,a+n);
  12. for(int i=1; i<n; i++){
  13. if(a[i]-a[i-1]>1){
  14. cout<<"NO"<<endl;
  15. flag=1;
  16. break;
  17. }
  18. }
  19. if(!flag){cout<<"YES"<<endl;}
  20. }
  21. }

                        OR

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int t; cin>>t;
  6. while(t--){
  7. int n; cin>>n;
  8. int MIN = INT_MAX;
  9. int MAX = INT_MIN;
  10. set<int> s;
  11. for(int i=0; i<n; i++){
  12. int a; cin>>a;
  13. s.insert(a);
  14. MIN = min(MIN,a);
  15. MAX = max(MAX,a);
  16. }
  17. cout<<(MAX-MIN+1 == s.size() ? "YES" : "NO")<<endl;
  18. }
  19. }



53. Restoring Three Numbers

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. long long p,q,r,s;
  5. cin>>p>>q>>r>>s;
  6. long long sum=(p+q+r+s)/3;
  7. for(int i : {p,q,r,s}){
  8. if(i<sum)
  9. cout<<sum-i<<' ';
  10. }
  11. }



52. Buy a Shovel

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int k,r;
  5. cin>>k>>r;
  6. for(int i=1; i<=10; i++){
  7. if(i*k%10==0 or i*k%10==r)
  8. {cout<<i;break;}
  9. }
  10. }



51. Vasya the Hipster

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int a,b;
  5. cin>>a>>b;
  6. cout<<min(a,b)<<" "<<abs(a-b)/2;
  7. }



50.  The New Year: Meeting Friends

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int a[3];
  5. cin>>a[0]>>a[1]>>a[2];
  6. sort(a,a+3);
  7. cout<<a[2]-a[0];
  8. }



49. Sum of Round Numbers

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int t,n; cin>>t;
  5. while(t--){
  6. cin>>n; //input taken
  7. vector<int> v; //output store
  8. int d=10; //divisor
  9. while(n){
  10. if(n%d){
  11. v.push_back(n%d);
  12. n = n - (n%d);
  13. }
  14. d = d*10;
  15. }
  16. cout<<v.size()<<'\n';
  17. for(auto x:v) {
  18. cout<<x<<" ";
  19. }
  20. cout<<'\n';
  21. }
  22. }



48. New Year and Hurry

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int n, k, problem=0, solved=0;
  5. cin>>n>>k;
  6. k=240-k;
  7. for(int i=1; i<=n; i++){
  8. problem+=i;
  9. if(problem*5<=k) solved=i;
  10. else break;
  11. }
  12. cout<<solved;
  13. }



47. I_love_\%username\%

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int n;
  5. cin>>n;
  6. int i;
  7. cin>>i;
  8. int max=i,min=i,cnt=0;
  9. while(n--){
  10. cin>>i;
  11. if(i>max) max=i, cnt++;
  12. if(i<min) min=i, cnt++;
  13. }
  14. cout<<cnt;
  15. }



46. Police Recruits

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int n;
  5. cin>>n;
  6. int a[n],cnt=0,pol=0;
  7. for(int i=0; i<n; i++){
  8. cin>>a[i];
  9. }
  10. for(int i=0; i<n; i++){
  11. if(a[i]==-1 && pol==0) cnt++;
  12. else if(a[i]!=-1) pol+=a[i];
  13. else pol--;
  14. }
  15. cout<<cnt;
  16. }

                                OR

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int n;
  5. cin>>n;
  6. int i,cnt=0,sum=0;
  7. while(n--){
  8. cin>>i;
  9. if(sum+i<0) cnt++;
  10. else sum+=i;
  11. }
  12. cout<<cnt;
  13. }



45. Fox And Snake

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int n,m;
  5. cin>>n>>m;
  6. for(int i=0;i<n; i++){
  7. for(int j=0;j<m; j++){
  8. cout<<((i%2==0 || (i%4==1 && j==m-1) || (i%4==3 && j==0))?'#':'.');
  9. }
  10. cout<<endl;
  11. }
  12. }



44. Amusing Joke

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. string a,b,c;
  5. cin>>a>>b>>c;
  6. a+=b;
  7. sort(a.begin(),a.end());
  8. sort(c.begin(),c.end());
  9. cout<<(a==c?"YES":"NO");
  10. }



43. Candies and Two Sisters

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int t; cin>>t;
  5. while(t--){
  6. int n; cin>>n;
  7. cout<<(n-1)/2<<'\n';
  8. }
  9. }



42. Anton and Polyhedrons

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. long long int n, ans=0;
  5. cin>>n;
  6. while(n--){
  7. string s; cin>>s;
  8. if(s[0]=='T') ans+=4;
  9. else if(s[0]=='C') ans+=6;
  10. else if(s[0]=='O') ans+=8;
  11. else if(s[0]=='D') ans+=12;
  12. else ans+=20;
  13. }
  15. cout<<ans;
  16. }



41. Games

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int n;
  5. cin >> n; // n teams
  6. int a[n], b[n];
  7. int ans = 0;
  9. for (int i = 0; i < n; i++) {
  10. cin >> a[i];
  11. cin >> b[i];
  12. }
  13.  
  14. for (int i = 0; i < n; i++) {
  15. for (int k = 0; k < n; k++) {
  16. if (a[i] == b[k])
  17. ans++;
  18. }
  19. }
  20.  
  21. cout << ans;
  22. return 0;
  23. }



40. Hit the Lottery

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int n,ans=0;
  6. cin>>n;
  7. for(int denom : {100,20,10,5,1}){
  8. ans+=n/denom;
  9. n%=denom;
  10. }
  11. cout<<ans;
  12. }



39. Anton and Letters

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. set <char> s;
  6. set <char> i = {'{', '}', ','};
  7. char c;
  8. while(cin>>c) {
  9. if(i.find(c)==i.end())
  10. s.insert(c);
  11. }
  12. cout<<s.size();
  13. }
  14.  
  15. //i.find(c) is used to check whether the character c is in the i set.
  16. //The find function returns an iterator that points to the position of c
  17. //in the set if it is found, or it returns i.end() if c is not in the set!



38. Insomnia cure

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int k,l,m,n,d,cnt=0;
  6. cin>>k>>l>>m>>n>>d;
  7. for(int i=1; i<=d; i++)
  8. if(i%k==0 or i%l==0 or i%m==0 or i%n==0) cnt++;
  9. cout<<cnt;
  11. }



37. Pangram

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int n; cin>>n;
  6. set<int> atoz;
  7. for(int i=0;i<n;i++){
  8. char c;
  9. cin>>c;
  10. atoz.insert(tolower(c));
  11. }
  12. cout<<(atoz.size()==26?"YES":"NO");
  13. }



36. Arrival of the General

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int n,a[100];
  6. cin>>n;
  7. int i_min=0, i_max=0;
  8. for(int i=0;i<n;i++){
  9. cin>>a[i];
  10. if(a[i]>a[i_max]) i_max=i;
  11. if(a[i]<=a[i_min]) i_min=i;
  12. }
  13. cout<<(n-1)-i_min + i_max-0 - (i_min<i_max);
  14. }


35. Divisibility Problem

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int t; cin>>t;
  6. while(t--){
  7. int a,b;
  8. cin>>a>>b;
  9. if(a%b==0) cout<<0<<endl;
  10. else
  11. cout<<((a/b)+1)*b - a<<endl;
  12. }
  13. }



34. I Wanna Be the Guy

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int n; cin>>n;
  6. set<int> s;
  7.  
  8. for(int i=1; i<=2; i++){
  9. int pq; cin>>pq;
  10. for(int i=1; i<=pq; i++){
  11. int a; cin>>a;
  12. s.insert(a);
  13. }
  14. }
  15. if(s.size()==n)
  16. cout<<"I become the guy.";
  17. else
  18. cout<<"Oh, my keyboard!";
  19.  
  20. }



33. Hulk

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int n; cin>>n;
  6. string s;
  7.  
  8. for(int i=1; i<=n; i++){
  9.  
  10. if(i%2!=0) s+="I hate ";
  11. else s+="I love ";
  12.  
  13. if(i==n) s+="it";
  14. else s+="that ";
  15. }
  17. cout<<s;
  18.  
  19. }



32. Is your horseshoe on the other hoof?

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int a[4], colors=0;
  5. for(int i=0;i<4;i++){
  6. cin>>a[i];
  7. }
  8. sort(a,a+4);
  9. for(int i=1;i<4;i++){
  10. if(a[i-1]==a[i]) colors++;
  11. }
  12. cout<<colors;
  13. }

                                            OR


  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. set<int> s;
  5. for(int i=0; i<4; i++){
  6. int color;
  7. cin>>color;
  8. s.insert(color);
  9. }
  10. cout<<4-s.size()<<endl;
  11. return 0;
  12. }



31. Ultra-Fast Mathematician 

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. string a,b;
  5. cin>>a>>b;
  6. for(int i=0; i<a.size(); i++){
  7. if(a[i]==b[i]) cout<<"0";
  8. else cout<<"1";
  9. }
  10. return 0;
  11. }



30. Drinks

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. float n,percent=0,tot=0;
  5. cin>>n;
  6. for(int i=0; i<n; i++){
  7. cin>>percent;
  8. tot+=percent;
  9. }
  10. cout<<tot/n;
  12. }


29. Calculating Function

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. long long int n;
  5. cin>>n;
  6. if(n%2==0)
  7. cout<< n/2;
  8. else
  9. cout<< (n-1)/2- n;
  10. }


28. Presents

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int n, gift, a[100];
  5. cin>>n;
  6. for(int i=1;i<=n;i++){
  7. cin>>gift;
  8. a[gift] = i;
  9. }
  10. for(int i=1; i<=n; i++)
  11. cout<<a[i]<<" ";
  12. }



27. Magnets

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int n, x, y, grp=1;
  5. cin>>n>>x;
  6. for(int i=1; i<n; i++){
  7. cin>>y;
  8. if(y!=x) grp+=1;
  9. x=y;
  10. }
  11. cout<<grp;
  12. }



26. George and Accommodation

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int n; cin>>n;
  5. int c=0;
  6. while(n--){
  7. int a,b;
  8. cin>>a>>b;
  9. if(a<=b-2) c++;
  10. }
  11. cout<<c<<endl;
  12.  
  13. }


25. In Search of an Easy Problem

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int n; cin>>n;
  5. int rating = 0;
  6. int opinion;
  7. for(int i=0; i<n; i++)
  8. {
  9. cin>>opinion;
  10. rating |= opinion;
  11. }
  12. if(rating) cout<<"HARD";
  13. else cout<<"EASY";
  14.  
  15. }



24. Beautiful Year

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int n; cin>>n;
  5. n=n+1;
  6. while(true){
  7. int o = n%10;
  8. int te = n/10%10;
  9. int h = n/100%10;
  10. int th = n/1000%10;
  11. if(o!=te && o!=h && o!=th && te!=h && te!=th && h!=th) {
  12. cout<<n;
  13. return 0;
  14. }
  15. else n++;
  16. }
  17. }

                                                    OR

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. bool hasDistinctDigits(int n){
  5. int o = n%10;
  6. int te = n/10%10;
  7. int h = n/100%10;
  8. int th = n/1000%10;
  9. if(o!=te && o!=h && o!=th && te!=h && te!=th && h!=th)
  10. return true;
  11. else return false;
  12. }
  13.  
  14.  
  15. int main(){
  16. int n;
  17. cin>>n;
  18. n=n+1;
  19. while(!hasDistinctDigits(n)){
  20. n+=1;
  21. }
  22. cout<<n;
  23. }



23. Queue at the School

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int n,t; string s;
  5. cin>>n>>t>>s;
  6. while(t--)
  7. for(int i=0; i<n-1; i++)
  8. if(s[i]=='B' && s[i+1]=='G')
  9. {s[i]='G'; s[i+1]='B'; i++;}
  10. cout<<s;
  11. }



22. Vanya and Fence

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int no_of_friends, height_of_fence, road_width=0, individual_height;
  5. cin>>no_of_friends>>height_of_fence;
  6. for(int i=0; i<no_of_friends; i++)
  7. {
  8. cin>>individual_height;
  9. if(individual_height>height_of_fence)
  10. road_width+=2;
  11. else road_width+=1;
  12. }
  13. cout<<road_width;
  14. }


21. Tram

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int n;
  5. cin>>n;
  7. int cnt=0, max=0;
  8. while(n--){
  9. int in, out;
  10. cin>>out>>in;
  11. cnt += in-out;
  12. if(cnt > max) max = cnt;
  13. }
  14. cout<<max<<endl;
  15. }


20.  Translation

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. main(){
  5. string a,b; cin>>a>>b;
  6. reverse(a.begin(), a.end());
  7. cout<<(a==b?"YES":"NO");
  8. }


19. Anton and Danik

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int n; cin>>n;
  6. string s; cin>>s;
  7. int a_count=0,d_count=0;
  9. for(auto i:s)
  10. a_count+=(i=='A'), d_count+=(i=='D');
  12. if(a_count>d_count) cout<<"Anton";
  13. else if(a_count==d_count) cout<<"Friendship";
  14. else cout<<"Danik";
  16. return 0;
  17. }



18. Nearly Lucky Number

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. string s; cin>>s;
  6. int c=0;
  7. for(int i=0; i<s.length(); i++){
  8. if(s[i]=='4' || s[i]=='7')
  9. c++;
  10. }
  11. cout<< ((c==4||c==7)?"YES":"NO");
  12. }


17. Wrong Subtraction

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int n,k;
  6. cin>>n>>k;
  7. for(int i=1; i<=k; i++){
  8. if(n%10==0) n/=10;
  9. else n-=1;
  10. }
  11. cout<<n;
  12. }



16. Word

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. string s; cin>>s;
  6. int dom=0;
  7. for(int i=0; i<s.size(); i++){
  8. if(isupper(s[i])) dom++;
  9. else dom--;
  10. }
  11. if(dom>0)
  12. for(auto &c:s) c=toupper(c);
  13. else
  14. for(auto &c:s) c=tolower(c);
  15. cout<<s<<endl;
  16. }


15. Elephant

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. long long int n;
  6. cin>>n;
  7. long long int cnt=0;
  8. if(n%5==0)
  9. cout<<n/5<<endl;
  10. else
  11. cout<<n/5+1<<endl;
  12. }


14.  Soldier and Bananas

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int k,n,w;
  6. cin>>k>>n>>w;
  7. cout<<max(0, (k*w*(w+1)/2 - n));
  8. }


13. Bear and Big Brother

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int a,b,years=0;
  6. cin>>a>>b;
  7. while(a<=b){
  8. a*=3; b*=2; years++;
  9. }
  10. cout<<years;
  12. }


12. Stones on the Table

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int n, min_count=0;
  6. cin>>n;
  7. string s;
  8. cin>>s;
  9. for(int i=1; i<n; i++){
  10. if(s[i]==s[i-1])
  11. min_count+=1;
  12. }
  13. cout<<min_count;
  14. return 0;
  16. }


11. Boy or Girl

  1. #include <bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. char c;
  5. set<char> s;
  6. while(cin>>c)
  7. s.insert(c);
  8. cout<<(s.size()%2==0 ?"CHAT WITH HER!":"IGNORE HIM!");
  10. }



10. Word Capitalization

  1. #include <bits/stdc++.h> //easy way : s = input()
  2. using namespace std; //print(s[0].upper() + s[1:])
  3. int main(){
  4. string s; cin>>s;
  5. s[0]=toupper(s[0]);
  6. cout<<s;
  7. }

                                                                        OR

  1. #include <bits/stdc++.h>
  2. using namespace std;
  4. int main(){
  5. string s,r;
  6. cin>>s;
  7. stringstream iss(s);
  8. char a;
  9. iss>>a;
  10. a = toupper(a);
  11. cout<<a;
  12. iss>>r;
  13. cout<<r<<endl;
  14. return 0;
  15. }

                                                                        OR

  1. #include <bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. string s,r;
  6. cin>>s;
  7. stringstream iss(s);
  8. char a;
  9. iss>>a;
  10. a = char(a & ~32);
  11. cout<<a;
  12. getline(iss,r);
  13. cout<<r<<endl;
  14. return 0;
  15. }



9. Helpful Maths

  1. #include <bits/stdc++.h>
  2. using namespace std;
  4. typedef long long ll;
  5. typedef vector<int> vi;
  7. #define FOR(i, a) for (int i=0; i<a; i++)
  8. #define pb push_back
  9.  
  10. int main(){
  11.  
  12. string s;
  13. cin>>s;
  14. vi v;
  15.  
  16. FOR(i,s.length())
  17. { if(i%2==0) v.pb(s[i]-'0'); }
  18.  
  19. sort(v.begin(), v.end());
  21. FOR(i, v.size())
  22. { cout<< v[i];
  23. if(i!=v.size()-1)
  24. cout<<"+"; }
  26. return 0;
  27. }


8. Petya and Strings

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  6. string a,b;
  7. cin>>a>>b;
  9. for(int i=0;i<a.size();i++){
  10. a[i] = tolower(a[i]);
  11. b[i] = tolower(b[i]);
  12. if(a[i]<b[i]) {cout<<"-1"; return 0;}
  13. else if(a[i]>b[i]) {cout<<"1"; return 0;}
  14. }
  16. cout<<"0";
  17. return 0;
  19. }


7. Beautiful Matrix

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5.  
  6. for(int i=1; i<=5; i++){
  7. for(int j=1; j<=5; j++)
  8. {
  9. char s;
  10. cin>>s;
  11. if(s=='1'){
  12. cout<<abs(i-3) + abs(j-3);
  13. return 0;
  14. }
  15. }
  16. }
  17.  
  18. return 0;
  19. }


6. Bit++

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int t,cnt=0;
  6. cin>>t;
  8. while(t--){
  9. string s;
  10. cin>>s;
  11. if(s[1]=='+') cnt+=1;
  12. else cnt-=1;
  13. }
  14. cout<<cnt;
  15. return 0;
  16. }


5. Domino piling

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int m, n;
  6. cin>>m>>n;
  7. cout<<(m*n)/2;
  8. }


4. Next Round

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int k,n;
  6. cin>>n>>k;
  7. vector<int> v(n);
  8. for(int i=0;i<n;i++)
  9. cin>>v[i];
  11. int count=0, check = v[k-1];
  12. for(int i=0;i<n;i++){
  13. if(v[i]>=check && v[i]>0)
  14. count+=1;
  15. else break;
  16. }
  17. cout<<count;
  18. return 0;
  19. }



3. Team

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  6. int t, cnt=0;
  7. cin>>t;
  8.  
  9. while(t--){
  10. int a, b, c;
  11. cin>>a>>b>>c;
  12. if(a+b+c>=2) cnt++;
  13. }
  15. cout<<cnt<<endl;
  16. return 0;
  17.  
  18. }


2. Way Too Long Words

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int n;
  6. string s;
  7. cin>>n;
  8. while(n--){
  9. cin>>s;
  10. if(s.size() > 10){
  11. cout<< s[0] << s.size()-2 << s.back() <<endl;
  12. }
  13. else cout<<s<<endl;
  14. }
  15.  
  16. }


1. Watermelon

  1. #include<iostream>
  2. using namespace std;
  3.  
  4. int main() {
  5. int n;
  6. cin>>n;
  7. cout<<(n%2==0 && n>2 ? "YES" : "NO")<<endl;
  8. return 0;
  9. }


Journey Begins - Sep/09/2023 23:15