N,Q=map(int,input().split())
S=input()
from collections import Counter
from copy import deepcopy
cum=[Counter() for i in range(N+1)]
for i in range(N):
    cum[i+1]=deepcopy(cum[i])
    cum[i+1][S[i]]+=1
a_l=[chr(i) for i in range(97, 97+26)]
for i in range(Q):
    L,R,X=map(int,input().split())
    tmp_c=cum[R]-cum[L-1]
    tmp=0
    for j in a_l:
        if tmp<=X<=tmp+tmp_c[j]:
            print(j)
            break
        else:
            tmp+=tmp_c[j]