#include <iostream>
#include <algorithm>
#include <string>
#include <vector>
#include <cmath>
#include <map>
#include <queue>
#include <iomanip>
#include <set>
#include <tuple>
#define mkp make_pair
#define mkt make_tuple
#define rep(i,n) for(int i = 0; i < (n); ++i)
#define all(v) v.begin(),v.end()
using namespace std;
typedef long long ll;
const ll MOD=1e9+7;
template<class T> void chmin(T &a,const T &b){if(a>b) a=b;}
template<class T> void chmax(T &a,const T &b){if(a<b) a=b;}

int main(){
  cin.tie(0);
  ios::sync_with_stdio(false);

  int N,Q;
  cin>>N>>Q;
  string S;
  cin>>S;

  vector<vector<int>> alp(N+1,vector<int> (26,0));
  rep(i,N){
    rep(j,26) alp[i+1][j]=alp[i][j];
    alp[i+1][S[i]-'a']++;
  }

  rep(q,Q){
    int l,r,x;
    cin>>l>>r>>x;

    l--;r--;
    vector<int> cnt(26,0);
    rep(j,26) cnt[j]=alp[r+1][j]-alp[l][j];

    int sum=0;
    rep(j,26){
      if(sum+cnt[j]>=x){
        cout<<char('a'+j)<<"\n";
        break;
      }
      sum+=cnt[j];
    }
  }

  return 0;
}