"""


"""

import sys
from sys import stdin

alp = "abcdefghijklmnopqrstuvwxyz"

def bitadd(a,w,bit): #aにwを加える(1-origin)

    a += 1
    x = a
    while x <= (len(bit)-1):
        bit[x] += w
        x += x & (-1 * x)
 
def bitsum(a,bit): #ind 1～aまでの和を求める

    a += 1
    ret = 0
    x = a
    while x > 0:
        ret += bit[x]
        x -= x & (-1 * x)
    return ret

ans = []
N,Q = map(int,stdin.readline().split())

S = stdin.readline()[:-1]

b = [[0] * (N+5) for i in range(26)]

for i in range(1,N+1):

    c = ord(S[i-1])-ord('a')
    bitadd(i,1,b[c])

for loop in range(Q):

    L,R,X = map(int,stdin.readline().split())

    for i in range(26):

        X -= bitsum(R,b[i]) - bitsum(L-1,b[i])
        if X <= 0:
            ans.append(alp[i])
            break

print ("\n".join(ans))