巨佬帮我看看怎么错了……求改T^T

#include <bits/stdc++.h>

using  namespace std;
const int N=1e6+2;
int m;
string s;
set <string> a;
int l1,l2,r1,r2;
char x[N],y[N];
int xl,yl;
int main()
{
    cin>>s;
    cin>>m;
    while(m--)
    {
        cin>>l1>>l2>>r1>>r2;
        xl=l2-l1+1;
        yl=r2-r1+1;
        for(int i=l1;i<=l2;i++)
            x[i]=s[i];
        for(int i=l1;i<=l2;i++)
            y[i]=s[i];
        if(xl!=yl)
        {
            cout<<"No"<<endl;
             continue;
        }
        for(int i=1;i<=xl;i++)
            if(x[i]!=y[i])
            {
                cout<<"No"<<endl;
                continue;
            }
        cout<<"Yes"<<endl;
    }
    return 0;
}