using System;
using static System.Console;
using System.Linq;
using System.Collections.Generic;

class Program
{
    static int NN => int.Parse(ReadLine());
    static int[] NList => ReadLine().Split().Select(int.Parse).ToArray();
    static int[][] NArr(long n) => Enumerable.Repeat(0, (int)n).Select(_ => NList).ToArray();
    public static void Main()
    {
        Solve();
    }
    static void Solve()
    {
        var c = NList;
        var (n, q) = (c[0], c[1]);
        var s = ReadLine();
        var query = NArr(q);
        var cum = new int[n + 1][];
        cum[0] = new int[26];
        for (var i = 0; i < n; ++i)
        {
            cum[i + 1] = (int[]) cum[i].Clone();
            ++cum[i + 1][s[i] - 'a'];
        }
        var ans = new char[q];
        for (var i = 0; i < q; ++i)
        {
            var sub = 0;
            for (var j = 0; j < 26; ++j)
            {
                sub += cum[query[i][1]][j] - cum[query[i][0] - 1][j];
                if (sub >= query[i][2])
                {
                    ans[i] = (char)(j + 'a');
                    break;
                }
            }
        }
        WriteLine(string.Join("\n", ans));
    }
}