acwing 841 字符串哈希

#include<iostream>
#include<cstring>
#include<algorithm>
 
using namespace std ;
typedef unsigned long long ULL ;
const int N = 1e5 +10, P = 131  ;
char a[N];
ULL h[N] , p[N] ;
ULL get(int l ,int  r) {
  return h[r] - h[l-1] * p[r-l+1] ; 
}
int main(){
  int n , m ;
  cin >> n >> m ;
  scanf("%s",a+1) ;
  p[0] = 1 ;
  for(int i = 1 ; i <= n ; i++){
    h[i] = h[i-1]*P + a[i] ;
    p[i] = p[i-1] * P ;
  }
  while(m --){
    int x1 , y1 , x2, y2 ;
    cin >> x1 >> y1 >> x2 >> y2 ;
    if(get(x1,y1) == get(x2,y2)) {
      cout << "Yes" << endl ;
    }else cout << "No" << endl ;
  }
}