#include<iostream>
#include<string>
#include<vector>
#include<algorithm>
#include<math.h>
#include<cctype>
#include<cstdlib>
#define el endl 

using namespace std;

int func1(int n, int k, string s){
   for(int i=0;i<n;i++){
      if(s[i]!='0'){
         return -1;
      }
   }
   return 1;

}

int func(int n, int k){

   string s;cin>>s; 
   cout << s << el;
   int f = n-k;
   if (f == 0){
      return func1(n, k, s);
   }
   for(int i=0;i<f;i++){

      if(s[i] != s[i+k]){
         return -1;
      }
      else{
         s[i] = '0';
         s[i+k] = '0';
      }
   }
   for(int i=0;i<n;i++){
      if(s[i] != '0'){
         return -1;
      }
   }
   return 1;

}

int main(){
   int t;cin>>t;
   for (int i=0;i<t;i++){
      int n, k;cin>>n>>k;
     int q = func(n, k);
     if(q == -1){
      cout<<"NO"<<el;
     }
     else{
      cout<<"YES"<<el;
     }

   }
}

Please can anyone tell me what is wrong in this code? It is working fine on test case 1, but not on test case 2. IDK what is the problem.

hey, can you please tell me why is the test n=4, k=4, s=1100 is YES? if n-k=0 then i can go from 1 to n-k, that is 1 to 0, which makes no sense. there is no number less than zero, and greater than 1. so basically, we do not have i, and thus no i+k. we cannot make any changes in the given string, so it is YES only if the string is all zeros, but it is not, so the answer should be NO. I'm getting WA in this test. this is a test in test case 2. This problem is Tatar Show, problem B.

The name is CodeQUEEN. So is it for females only?