ll@N,@Q;
string@S;
ll@(L--,R,X)[Q],f[26];
rep(i,Q){
    rep(j,26)f[j]=0;
    rep(j,L[i],R[i])f[S[j]-'a']++;
    rep(j,26){
        if(X[i]-f[j]<=0){
            wt((char)(j+'a')),break;
        }else X[i]-=f[j];
    }
}