#include <bits/stdc++.h>
#include<atcoder/all>
using namespace atcoder;
#define rep(i, n) for(ll i = 0; i < n; i++)
#define rep2(i, m, n) for(ll i = m; i <= n; i++)
#define rrep(i, m, n) for(ll i = m; i >= n; i--)
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define MAX(x) *max_element(all(x))
#define MIN(x) *min_element(all(x))
#define SZ(a) ((ll)(a).size())
using namespace std;
typedef long long ll;
typedef pair<int, int> P;
const ll mod = 1000000007;
const int dx[4] = { -1, 1, 0, 0 };
const int dy[4] = { 0, 0, 1, -1 };
const int inf = 1e9 + 1;
const ll INF = 1e18 + 1;
const double pi = acos(-1);

using Graph = vector<vector<int>>;
Graph G;

typedef atcoder::modint1000000007 mint;
//typedef atcoder::modint998244353 mint;
//typedef modint mint;

int a[10010][30];
int sc[10010][30];

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int n, q; cin >> n >> q;
    string s; cin >> s;

    rep(i, n) a[i][s[i] - 'a']++;

    rep(i, n)rep(j, 26) sc[i + 1][j] = sc[i][j] + a[i][j];

    while (q--) {
        int l, r, x; cin >> l >> r >> x;
        int cur = 0;
        int pos;
        rep(i, 26) {
            if (cur + (sc[r][i] - sc[l - 1][i]) < x) {
                cur += sc[r][i] - sc[l - 1][i];
            }
            else {
                pos = i;
                break;
            }
        }
        for (char c = 'a'; c <= 'z'; c++) {
            if (c - 'a' == pos) cout << c << endl;
        }
    }

}