Codeforces Round #215 (Div. 2) C. Sereja and Algorithm

#include <iostream>
#include <vector>
#include <algorithm>
#include <string>

using namespace std;

int main(){
    string s ;
    cin >>s;
    int m;
    cin >>m;
    vector<int> l(m),r(m);
    for(int i =  ; i < m ; ++ i )
        cin >> l[i]>>r[i];

    int n = s.length();
    vector<int> x(n+,),y(n+,),z(n+,);
    for(int i = ; i < n; ++ i){
        x[i+] =x[i];
        y[i+] = y[i];
        z[i+] = z[i];
        if(s[i] == 'x')  x[i+]++;
        else if(s[i] == 'y') y[i+]++;
        else z[i+]++;
    }

    for(int i =  ; i < m ; ++ i){
        if(r[i]-l[i]+ < ) cout<<"YES"<<endl;
        else{
            vector<int> num(,);
            num[] = x[r[i]]-x[l[i]-];
            num[] = y[r[i]]-y[l[i]-];
            num[] = z[r[i]]-z[l[i]-];
            sort(num.begin(),num.end());
            if((num[] == num[] && num[] == num[])||
               (num[]-num[] ==  && num[] == num[]) ||
               (num[]-num[] ==  && num[] - num[] == ))
                cout<<"YES"<<endl;
            else cout<<"NO"<<endl;
        }
    }
    return ;
}