View Code of Problem 4062

#include<bits/stdc++.h>
using namespace std;
int main(){
	int t;cin>>t;
	while(t--){
		string s1,s2;
		cin>>s1>>s2;
		int l;
		cin>>l;
		for(int i=0;i<s1.size();){
			if(s1[i]==s2[i]){
				s1.erase(s1.begin()+i);
				s2.erase(s2.begin()+i);
			}
			else
			++i;
		}
		int x=0,y=0;
		for(int i=0;i<s1.size();++i){
			if(s1[i]=='x')x++;
			else y++;
			if(s2[i]=='x')x++;
			else y++;
		}
		if(x%2==0&&y%2==0){
			if(s1.size()<=l*2)
			cout<<"YES"<<endl;
			else
			cout<<"NO"<<endl;
		}
		else
		cout<<"NO"<<endl;
	}
	return 0;
}