#include <string>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;
 
const long long INF = 3LL << 60;
 
// range add/max lazy segment tree
class lazy_segtree {
private:
	int sz;
	vector<long long> val;
	vector<long long> lazy;
	void push(int k) {
		if (lazy[k] != 0) {
			val[k] += lazy[k];
			if (k < sz) {
				lazy[k * 2 + 0] += lazy[k];
				lazy[k * 2 + 1] += lazy[k];
			}
			lazy[k] = 0;
		}
	}
	void add(int a, int b, int k, int l, int r, long long x) {
		push(k);
		if (a <= l && r <= b) {
			lazy[k] += x;
			push(k);
			return;
		}
		if (r <= a || b <= l) {
			return;
		}
		add(a, b, k * 2 + 0, l, (l + r) >> 1, x);
		add(a, b, k * 2 + 1, (l + r) >> 1, r, x);
		val[k] = max(val[k * 2 + 0], val[k * 2 + 1]);
	}
	long long rangemax(int a, int b, int k, int l, int r) {
		push(k);
		if (a <= l && r <= b) {
			return val[k];
		}
		if (r <= a || b <= l) {
			return -INF;
		}
		long long lc = rangemax(a, b, k * 2 + 0, l, (l + r) >> 1);
		long long rc = rangemax(a, b, k * 2 + 1, (l + r) >> 1, r);
		return max(lc, rc);
	}
public:
	lazy_segtree() : sz(0), val(vector<long long>()), lazy(vector<long long>()) {}
	lazy_segtree(int n) {
		sz = 1;
		while (sz < n) {
			sz *= 2;
		}
		val = vector<long long>(sz * 2, 0);
		lazy = vector<long long>(sz * 2, 0);
	}
	void add(int l, int r, long long x) {
		add(l, r, 1, 0, sz, x);
	}
	long long rangemax(int l, int r) {
		return rangemax(l, r, 1, 0, sz);
	}
};

int main() {
	int N, Q; string S;
	cin >> N >> Q >> S;
	vector<int> A = { 0 };
	for (int i = 1; i < N; i++) {
		if (S[i - 1] != S[i]) {
			A.push_back(i);
		}
	}
	A.push_back(N);
	vector<int> sum(N + 1);
	for (int i = 0; i < N; i++) {
		sum[i + 1] = sum[i] + (S[i] == '1' ? 1 : -1);
	}
	lazy_segtree seg(N);
	for (int i = 0; i < int(A.size()) - 1; i++) {
		seg.add(A[i], A[i + 1], A[i + 1] - A[i]);
	}
	for (int i = 0; i < Q; i++) {
		int L, R, K;
		cin >> L >> R >> K;
		L -= 1;
		int p1 = lower_bound(A.begin(), A.end(), L + 1) - A.begin();
		int p2 = lower_bound(A.begin(), A.end(), R) - A.begin();
		int maxwidth = 0;
		if (p1 == p2) {
			maxwidth = R - L;
		}
		else if (p2 - p1 == 1) {
			maxwidth = max(A[p1] - L, R - A[p2 - 1]);
		}
		else {
			maxwidth = max(A[p1] - L, R - A[p2 - 1]);
			maxwidth = max(maxwidth, (int)seg.rangemax(p1, p2 - 1));
		}
		if (maxwidth < K) {
			cout << R - L << '\n';
		}
		else {
			int x = sum[R] - sum[L];
			x = (x >= 0 ? x % (2 * K - 1) : ((2 * K - 1) - (-x) % (2 * K - 1)) % (2 * K - 1));
			cout << max(x - 1, (2 * K - 1) - x - 1) << '\n';
		}
	}
	return 0;
}