#include<stdio.h>
char s[10004];
int l[10004], r[10004], x[10004];
int count[30][10004];
int main()
{
	int n, q;
	scanf("%d %d", &n, &q);
	scanf("%s", s);
	int i, j;
	for (i = 0; i < q; i++)
		scanf("%d %d %d", &l[i], &r[i], &x[i]);
	for (i = 0; i < 30; i++)
		for (j = 0; j < 10004; j++)
			count[i][j] = 0;
	for (i = 0; i < n; i++)
	{
		for (j = 0; j < 30; j++)
			count[j][i + 1] = count[j][i];
		count[s[i] - 'a'][i + 1]++;
	}
	int cnt;
	for (i = 0; i < q; i++)
	{
		cnt = 0;
		for (j = 0;; j++)
		{
			cnt += count[j][r[i]] - count[j][l[i] - 1];
			if (cnt >= x[i])
			{
				printf("%c\n", 'a' + j);
				break;
			}
		}
	}
	return 0;
}