#include<bits/stdc++.h>
using namespace::std;

const int N = 10000 + 5;
const int E = 26;

int n;
int q;
char s[N];
int ac[E][N];

void preprocess(){
	for(int i = 1; i <= n; i++){
		for(int j = 0; j < E; j++){
			ac[j][i] = ac[j][i - 1];
		}
		ac[s[i] - 'a'][i] += 1;
	}
}

char solve(int l, int r, int k){
	int sum = 0;
	for(int i = 0; i < E; i++){
		int here = ac[i][r] - ac[i][l - 1];
		if(sum + here >= k) return i + 'a';
		sum += here;
	}
}

int main(){
	scanf("%d %d", &n, &q);
	scanf("%s", s + 1);
	preprocess();
	int l, r, k;
	while(q--){
		scanf("%d %d %d", &l, &r, &k);
		putchar(solve(l, r, k));
		puts("");
	}
	return 0;
}