N, Q = map(int, input().split())
S = input()

X = [[] for _ in range(N)]

for i in range(N):
    for j in range(i, N):
        X[i].append([])
        s = ''.join(sorted(S[i:(j+1)]))
        for k in range(j-i+1):
            X[i][j-i].append(s[k])

for i in range(Q):
    l, r, x = map(int, input().split())
    print(X[l-1][r - l][x-1])