Codeforces : From Newbie to Expert (1000-Rated)

 so ... I will be sharing all solutions here (recent solutions at the top, or find by ctrl+f)

                                


1000 Rated Problems Link : ProblemSet

Video Explanations : Check Here



14. New Year Candles

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



13. Move Brackets

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int t; cin>>t;
  6. while(t--){
  7. int n; string s; cin>>n>>s;
  8. int ans=0, cnt=0;
  9. for(auto &i:s){
  10. if(i=='(') cnt++;
  11. else cnt--;
  13. if(cnt<0) // ))(( ())( )()(
  14. { ans++; cnt=0;}
  15. }
  16. cout<<ans<<endl;
  17. }
  18. }



12. New Year Transportation

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



11.  Football

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

                                                        OR

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int n; cin>>n;
  6. map<string, int> m;
  7. for(int i=0; i<n; i++){
  8. string s; cin>>s;
  9. m[s]++;
  10. }
  11. int mx = 0; string ans;
  12. for(auto a:m)
  13. if(a.second > mx)
  14. mx = a.second, ans = a.first;
  15. cout<<ans;
  16. }


10. Raising Bacteria

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


9. Xenia and Ringroad

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. #define ll long long
  4. int main(){
  5. ll n, m; cin>>n>>m;
  6. ll cnt=0, init=1;
  7. for(int i=0; i<m; i++) {
  8. int loc; cin>>loc;
  9. if(loc>=init) cnt+= loc-init;
  10. else cnt+= n-(init-loc);
  11. init = loc;
  12. }
  13. cout<<cnt;
  14. }



8. Dragons

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main(){
  5. int s, n; cin>>s>>n;
  6. pair<int, int> a[n];
  8. for(int i=0; i<n; i++)
  9. cin>>a[i].first>>a[i].second;
  11. sort(a, a+n);
  13. for(int i=0; i<n; i++)
  14. {
  15. if(s<=a[i].first) {cout<<"NO"; return 0; }
  16. else s+=a[i].second;
  18. }
  19. cout<<"YES";
  20. }



7. cAPS lOCK

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. string s; cin>>s;
  5. bool capslock = true;
  6. for(int i=1; i<s.length(); i++)
  7. if(s[i]>'Z') capslock=false;
  8.  
  9. if(capslock==true)
  10. for(int i=0; i<s.length(); i++)
  11. s[i]^=32;
  12.  
  13. cout<<s;
  14. }


6.  Expression

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



5. Lucky Division

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int n; cin>>n;
  5. bool flag = 1;
  6. int a[12] = {4, 7, 47, 74, 44, 444, 447, 474, 477, 777, 774, 744};
  7. for(int i=0; i<12; i++)
  8. if(n%a[i]==0) flag=0;
  9. cout<<(flag==0?"YES":"NO");
  10. }


4. Chat room

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


3. Young Physicist

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. int n; cin>>n;
  5. int sx=0, sy=0, sz=0;
  6. int x[n], y[n], z[n];
  7. for(int i=0; i<n; i++){
  8. cin>>x[i]>>y[i]>>z[i];
  9. sx+=x[i], sy+=y[i], sz+=z[i];
  10. }
  11. cout<<(sx||sy||sz?"NO":"YES");
  12. }



2. String Task

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. int main(){
  4. string s; cin>>s;
  5. string v = "aeiouyAEIOUY";
  6. for(int i=0; i<s.length(); i++){
  7. int flag=1;
  8. for(int j=0; j<12; j++)
  9. if(s[i]==v[j]) flag=0;
  10. if(flag){
  11. if(s[i]<'a') s[i]+='a'-'A';
  12. cout<<"."<<s[i];
  13. }
  14. }
  15. }



1.  Theatre Square

  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. #define ll long long
  4. int main(){
  5. ll n, m, a; cin>>n>>m>>a;
  6. n = n/a + (n%a!=0);
  7. m = m/a + (m%a!=0);
  8. cout<<n*m<<endl;
  9. }