
#include <bits/stdc++.h>
using namespace std;

using ll = long long;
using p_int = pair<int, int>;

int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);

    int n, h;
    cin >> n >> h;

    int a, b[n];
    int max_a = 0;
    for (int i = 0; i < n; ++i) {
        cin >> a >> b[i];
        max_a = max(max_a, a);
    }

    sort(b, b +n, greater<>());
    // sort(b, b +n, [](int x, int y) { return x > y;});

    int count = 0;
    for (auto sub_b: b) {
        if (h <= 0) {
            cout << count << '\n';
            return 0;
        }
        if (sub_b < max_a) break;
        h -= sub_b;
        count++;
    }

    cout << count + ceil(h * 1.0 / max_a) << '\n';
    
    return 0;
}
