#include <iostream>
#include <string>
#include <algorithm>
#include <functional>
#include <vector>
#include <stack>
#include <queue>
#include <set>
#include <map>
#include <tuple>
#include <cstdio>
#include <cmath>
#include <cassert>
#include <atcoder/modint>
#define rep(i, n) for(i = 0; i < n; i++)
#define int long long
using namespace std;
using namespace atcoder;
using mint = modint998244353;

signed main() {
	int n, m;
	cin >> n >> m;
	
	int i;
	vector<int> a(n), b(n);
	rep(i, n) {
		scanf("%lld%lld", &a[i], &b[i]);
	}

	vector<int> f(n + 1);	//f(x): a[i] + x * b[i] > Mを満たすiの個数
	rep(i, n) {
		int c = ((m + 1 - a[i]) + b[i] - 1) / b[i];
		if (c <= n) f[c]++;
	}
	rep(i, n) f[i + 1] += f[i];

	int ans = 0;
	for (i = 1; i <= n; i++) {
		int res = (f[i] + i - 1) / i;
		ans = max(ans, res);
	}

	cout << ans << endl;
	return 0;
}