#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
typedef long long ll;
typedef pair<ll,ll> P;
typedef modint998244353 mint;
#define rep(i,a,b) for(ll i=a;i<b;i++)
#define rrep(i,a,b) for(ll i=a;i>=b;i--)
const ll inf=1e18;
ll n,q;
string s;
ll l,r,x;
ll c[100005][30];
ll cnt[30];
int main(void){
    cin.tie(0);
    ios::sync_with_stdio(0);
    cin>>n>>q>>s;
    rep(i,0,n){
        rep(j,0,30){
            c[i+1][j]=c[i][j];
        }
        c[i+1][s[i]-'a']++;
    }
    while(q--){
        cin>>l>>r>>x;
        l--;
        ll cur=0;
        rep(i,0,30){
            cnt[i]=c[r][i]-c[l][i];
            cur+=cnt[i];
            if(cur>=x){
                cout<<char('a'+i)<<endl;
                break;
            }
        }
    }

}