# alphabet count tableを用意するか
alphabets = 'abcdefghijklmnopqrstuvwxyz'
dic = {}
for i in range(26):
    dic[alphabets[i]] = i

N, Q = map(int, input().split())
S = input()
dp = [[0]*26 for i in range(N+1)]
for i in range(1, N+1):
    letter_num = dic[S[i-1]]
    for j in range(26):
        dp[i][j] = dp[i-1][j]
    dp[i][letter_num] += 1
    #print(dp[i])

for q in range(Q):
    l, r, x = map(int, input().split())
    count = [0]*26
    for i in range(26):
        count[i] = dp[r][i]-dp[l-1][i]
    x_remainder = x
    for i in range(26):
        if count[i] < x_remainder:
            x_remainder -= count[i]
        elif count[i] >= x_remainder:
            #print(count)
            print(alphabets[i])
            break