import sys
import io, os
input = sys.stdin.readline

n, q = map(int, input().split())
s = input().rstrip()
#print(s)
C = [[0]*(n+1) for i in range(26)]
for i, c in enumerate(s):
    C[ord(c)-ord('a')][i+1] += 1
for j in range(26):
    for i in range(1, n+1):
        C[j][i] += C[j][i-1]
#print(C[0])
for i in range(q):
    l, r, x = map(int, input().split())
    l, r = l-1, r-1
    cnt = 0
    for j in range(26):
        cnt += C[j][r+1]-C[j][l]
        if cnt >= x:
            p = j
            break
    #print(p)
    ans = chr(p+ord('a'))
    print(ans)