#include <bits/stdc++.h>
inline int read() {
  int f = 1, x = 0;
  char c = getchar();
  while (c < '0' || c > '9') {
    if (c == '-') f = -1;
    c = getchar();
  }
  while (c <= '9' && c >= '0') {
    x = x * 10 + c - '0';
    c = getchar();
  }
  return x * f;
}
inline void file() {
  freopen("1.in", "r", stdin);
  freopen("1.out", "w", stdout);
}
using namespace std;
const long long maxn = 1e6 + 10;
long long a[maxn], b[maxn];
int main() {
  long long k, n, h;
  scanf("%lld%lld", &n, &h);
  for (register long long i = 1; i <= n; ++i) cin >> a[i] >> b[i];
  sort(b + 1, b + n + 1);
  sort(a + 1, a + n + 1);
  for (register long long i = 1; i <= n; ++i) b[i] = max(b[i], a[n]);
  long long ovo = 0;
  for (register long long i = n; i >= 1; --i) {
    ovo += b[i];
    if (ovo >= h) printf("%lld", n - i + 1);
  }
  if (ovo < h) {
    h -= ovo;
    printf("%lld", n + (h / a[n]) + (h % a[n] == 0 ? 0 : 1));
  }
  return 0;
}
