import sys
import collections
def resolve():
    readline = sys.stdin.readline
    n,q = map(int,readline().split())
    s = readline().strip()
    orda = ord('a')
    tmp = [0]*26
    sumchr = [None]*(len(s)+1)
    sumchr[0] = [0]* 26

    for i, c in enumerate(s,1):
        tmp[ord(c)-orda] += 1
        sumchr[i] = [cnt for cnt in tmp]

    deq = collections.deque()
    for _ in range(q):
        l,r,x = map(int,readline().split())
        chrcnt = [ri-li for li,ri in zip(sumchr[l-1],sumchr[r])]

        cnt = 0
        for i,cnti in enumerate(chrcnt,orda):
            cnt += cnti
            if x <= cnt:
                deq.append(chr(i))
                break
    print(*deq,sep='\n')
resolve()