#include <bits/stdc++.h>
using namespace std;

#define ll long long
#define rep(i, n) for (int i = 0; i < (n); i++)
#define P pair<int, int>

int main() {
  int n, q;
  cin >> n >> q;
  string s;
  cin >> s;
  vector<vector<int>> v(26, vector<int>(10005, 0));
  vector<vector<int>> sum(26, vector<int>(10005, 0));

  rep(i, n) {
    v[s[i]-'a'][i] = 1;
  }
  rep(i, 26) {
    rep(j, n) {
      sum[i][j+1] = sum[i][j] + v[i][j];
    }
  }
  rep(i, q) {
    int l, r, x;
    cin >> l >> r >> x;
    l--, r--;
    vector<int> cnt(26);
    rep(j, 26) cnt[j] = sum[j][r+1] - sum[j][l];
    int now = cnt[0];
    int ind = 0;
    while (now < x) {
      ind++;
      now += cnt[ind];
    }
    string ans;
    ans.push_back(ind+'a');
    cout << ans << endl;
  }

}