/*
このコード、と～おれ!
Be accepted!
∧＿∧　
（｡･ω･｡)つ━☆・*。
⊂　　 ノ 　　　・゜+.
　しーＪ　　　°。+ *´¨)
 　　　　　　　　　.· ´¸.·*´¨) ¸.·*¨)
		  　　　　　　　　　　(¸.·´ (¸.·'* ☆
*/

#include <cstdio>
#include <algorithm>
#include <string>
#include <cmath>
#include <cstring>
#include <vector>
#include <numeric>
#include <iostream>
#include <random>
#include <map>
#include <unordered_map>
#include <queue>
#include <regex>
#include <functional>
#include <complex>
#include <list>
#include <cassert>
#include <iomanip>
#include <set>
#include <stack>
#include <bitset>
#include <array>
#include <chrono>

//#pragma GCC target("arch=skylake-avx512")
//#pragma GCC target("avx2")
//#pragma GCC optimize("O3")
//#pragma GCC optimize("Ofast")
//#pragma GCC target("sse4")
//#pragma GCC optimize("unroll-loops")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#define repeat(i, n, m) for(int i = n; i < (m); ++i)
#define rep(i, n) for(int i = 0; i < (n); ++i)
#define printynl(a) printf(a ? "yes\n" : "no\n")
#define printyn(a) printf(a ? "Yes\n" : "No\n")
#define printYN(a) printf(a ? "YES\n" : "NO\n")
#define printim(a) printf(a ? "possible\n" : "imposible\n")
#define printdb(a) printf("%.50lf\n", a)
#define printLdb(a) printf("%.50Lf\n", a)
#define printdbd(a) printf("%.16lf\n", a)
#define prints(s) printf("%s\n", s.c_str())
#define all(x) (x).begin(), (x).end()
#define deg_to_rad(deg) (((deg)/360.0L)*2.0L*PI)
#define rad_to_deg(rad) (((rad)/2.0L/PI)*360.0L)
#define Please return
#define AC 0
#define manhattan_dist(a, b, c, d) (abs(a - c) + abs(b - d))

using ll = long long;
using ull = unsigned long long;

constexpr int INF = 1073741823;
constexpr int MINF = -1073741823;
constexpr ll LINF = ll(4661686018427387903);
constexpr ll MOD = 1e9 + 7;
constexpr ll mod = 998244353;
constexpr long double eps = 1e-6;
const long double PI = acosl(-1.0L);

using namespace std;

void scans(string& str) {
	char c;
	str = "";
	scanf("%c", &c);
	if (c == '\n')scanf("%c", &c);
	while (c != '\n' && c != -1 && c != ' ') {
		str += c;
		scanf("%c", &c);
	}
}

void scanc(char& str) {
	char c;
	scanf("%c", &c);
	if (c == -1)return;
	while (c == '\n') {
		scanf("%c", &c);
	}
	str = c;
}

double acot(double x) {
	return PI / 2 - atan(x);
}

ll LSB(ll n) { return (n & (-n)); }

template<typename T>
inline T chmin(T& a, const T& b) {
	if (a > b)a = b;
	return a;
}

template<typename T>
inline T chmax(T& a, const T& b) {
	if (a < b)a = b;
	return a;
}

//cpp_int
#if __has_include(<boost/multiprecision/cpp_int.hpp>)
#include <boost/multiprecision/cpp_int.hpp>
#include <boost/multiprecision/cpp_dec_float.hpp>
using namespace boost::multiprecision;
#else
using cpp_int = ll;
#endif

//atcoder library
#if __has_include(<atcoder/all>)
#include <atcoder/all>
//using namespace atcoder;
#endif

/*
	random_device seed_gen;
	mt19937 engine(seed_gen());
	uniform_int_distribution dist(1, 100);
*/


/*----------------------------------------------------------------------------------*/

/**
 * @brief Segment-Tree(セグメント木)
 * @docs docs/segment-tree.md
 */
template< typename Monoid, typename F >
struct SegmentTree {
	int sz;
	vector< Monoid > seg;

	const F f;
	const Monoid M1;

	SegmentTree(int n, const F f, const Monoid& M1) : f(f), M1(M1) {
		sz = 1;
		while (sz < n) sz <<= 1;
		seg.assign(2 * sz, M1);
	}

	void set(int k, const Monoid& x) {
		seg[k + sz] = x;
	}

	void build() {
		for (int k = sz - 1; k > 0; k--) {
			seg[k] = f(seg[2 * k + 0], seg[2 * k + 1]);
		}
	}

	void update(int k, const Monoid& x) {
		k += sz;
		seg[k] = x;
		while (k >>= 1) {
			seg[k] = f(seg[2 * k + 0], seg[2 * k + 1]);
		}
	}

	Monoid query(int a, int b) {
		Monoid L = M1, R = M1;
		for (a += sz, b += sz; a < b; a >>= 1, b >>= 1) {
			if (a & 1) L = f(L, seg[a++]);
			if (b & 1) R = f(seg[--b], R);
		}
		return f(L, R);
	}

	Monoid operator[](const int& k) const {
		return seg[k + sz];
	}

	template< typename C >
	int find_subtree(int a, const C& check, Monoid& M, bool type) {
		while (a < sz) {
			Monoid nxt = type ? f(seg[2 * a + type], M) : f(M, seg[2 * a + type]);
			if (check(nxt)) a = 2 * a + type;
			else M = nxt, a = 2 * a + 1 - type;
		}
		return a - sz;
	}

	template< typename C >
	int find_first(int a, const C& check) {
		Monoid L = M1;
		if (a <= 0) {
			if (check(f(L, seg[1]))) return find_subtree(1, check, L, false);
			return -1;
		}
		int b = sz;
		for (a += sz, b += sz; a < b; a >>= 1, b >>= 1) {
			if (a & 1) {
				Monoid nxt = f(L, seg[a]);
				if (check(nxt)) return find_subtree(a, check, L, false);
				L = nxt;
				++a;
			}
		}
		return -1;
	}

	template< typename C >
	int find_last(int b, const C& check) {
		Monoid R = M1;
		if (b >= sz) {
			if (check(f(seg[1], R))) return find_subtree(1, check, R, true);
			return -1;
		}
		int a = sz;
		for (b += sz; a < b; a >>= 1, b >>= 1) {
			if (b & 1) {
				Monoid nxt = f(seg[--b], R);
				if (check(nxt)) return find_subtree(b, check, R, true);
				R = nxt;
			}
		}
		return -1;
	}
};

template< typename Monoid, typename F >
SegmentTree< Monoid, F > get_segment_tree(int N, const F& f, const Monoid& M1) {
	return { N, f, M1 };
}

/*
* @title Mo's Algorithm
* @docs kyopro/docs/mo.md
*/

template<typename ADD_LEFT, typename DEL_LEFT, typename REM, typename ADD_RIGHT = ADD_LEFT, typename DEL_RIGHT = DEL_LEFT, typename T = int>
struct mo {
	int sqn, q, l, r, p;
	T ret;
	vector<tuple<int, int, int, int>> query;
	vector<char> ans;

	mo(const int& n, const int& q) : sqn((int)std::sqrt(n)), q(q), l(0), r(0), p(0), ret(get_segment_tree(26, plus<int>(), 0)), query(q), ans(q) {}

	inline void insert(const int& l, const int& r) {
		query[p] = { l, r, p };
		++p;
	}

	inline void read(const bool& oneindexed) {
		for (auto& [left, right, po, idx] : query) {
			scanf("%d%d%d", &left, &right, &po);
			if (oneindexed)--left;
			idx = p++;
		}
	}

	void build() {
		sort(all(query), [&](const tuple<int, int, int, int>& a, const tuple<int, int, int, int>& b) {
			if (get<0>(a) / sqn != get<0>(b) / sqn)return get<0>(a) < get<0>(b);
			return get<1>(a) < get<1>(b);
			});
	}

	void run(const ADD_LEFT& add_left, const ADD_RIGHT& add_right, const DEL_LEFT& del_left, const DEL_RIGHT& del_right, const REM& rem) {
		for (const auto& [ql, qr, p, qo] : query) {
			while (l > ql)add_left(--l, ret);
			while (r < qr)add_right(r++, ret);
			while (l < ql)del_left(l++, ret);
			while (r > qr)del_right(--r, ret);
			rem(qo, ans, ret, p);
		}
	}

	void run(const ADD_LEFT& add, const DEL_LEFT& del, const REM& rem) {
		run(add, add, del, del, rem);
	}

	char operator [](const int& idx) {
		return ans[idx];
	}

	void allrun(const bool& oneindexed, const ADD_LEFT& add_left, const ADD_RIGHT& add_right, const DEL_LEFT& del_left, const DEL_RIGHT& del_right, const REM& rem) {
		read(oneindexed);
		build();
		run(add_left, add_right, del_left, del_right, rem);
	}

	void allrun(const bool& oneindexed, const ADD_LEFT& add, const DEL_LEFT& del, const REM& rem) {
		allrun(oneindexed, add, add, del, del, rem);
	}

};


int main() {

	int n, q;
	scanf("%d%d", &n, &q);
	string s, t;
	scans(s);
	auto seg = get_segment_tree(26, plus<int>(), 0);
	seg.build();
	auto add = [&](const int& idx, decltype(seg)& ret) {
		ret.update(s[idx] - 'a', ret[s[idx] - 'a'] + 1);
	};
	auto del = [&](const int& idx, decltype(seg)& ret) {
		ret.update(s[idx] - 'a', ret[s[idx] - 'a'] - 1);
	};
	auto rem = [&](const int& num, vector<char>& ans, decltype(seg)& ret, const int& x) {
		int idx = ret.find_first(0, [&](const int& aa) {return aa >= x; });
		ans[num] = 'a' + idx;
	};
	mo<decltype(add), decltype(del), decltype(rem), decltype(add), decltype(del), decltype(seg)> m(n, q);
	m.allrun(true, add, del, rem);
	rep(i, q)printf("%c\n", m[i]);

	Please AC;
}