import std.conv, std.functional, std.range, std.stdio, std.string;
import std.algorithm, std.array, std.bigint, std.bitmanip, std.complex, std.container, std.math, std.mathspecial, std.numeric, std.regex, std.typecons;
import core.bitop;

class EOFException : Throwable { this() { super("EOF"); } }
string[] tokens;
string readToken() { for (; tokens.empty; ) { if (stdin.eof) { throw new EOFException; } tokens = readln.split; } auto token = tokens.front; tokens.popFront; return token; }
int readInt() { return readToken.to!int; }
long readLong() { return readToken.to!long; }
real readReal() { return readToken.to!real; }

bool chmin(T)(ref T t, in T f) { if (t > f) { t = f; return true; } else { return false; } }
bool chmax(T)(ref T t, in T f) { if (t < f) { t = f; return true; } else { return false; } }

int binarySearch(alias pred, T)(in T[] as) { int lo = -1, hi = cast(int)(as.length); for (; lo + 1 < hi; ) { const mid = (lo + hi) >> 1; (unaryFun!pred(as[mid]) ? hi : lo) = mid; } return hi; }
int lowerBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a >= val)); }
int upperBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a > val)); }




void main() {
  try {
    for (; ; ) {
      const N = readInt();
      const Q = readInt();
      const S = readToken();
      auto L = new int[Q];
      auto R = new int[Q];
      auto X = new int[Q];
      foreach (q; 0 .. Q) {
        L[q] = readInt() - 1;
        R[q] = readInt();
        X[q] = readInt();
      }
      
      foreach (q; 0 .. Q) {
        auto freq = new int[26];
        foreach (i; L[q] .. R[q]) {
          ++freq[S[i] - 'a'];
        }
        int now;
        foreach (a; 0 .. 26) {
          now += freq[a];
          if (now >= X[q]) {
            writeln(cast(char)('a' + a));
            break;
          }
        }
      }
    }
  } catch (EOFException e) {
  }
}