#pragma GCC optimize("Ofast")
  
#include <iostream>
#include <algorithm>
#include <vector>
#include <cstring>
#include <string>
#include <map>
#include <unordered_map>
#include <queue>
#include <stack>
#include <deque>
#include <set>
#include <unordered_set>
#include <list>
#include <tuple>
#include <iomanip>
#include <climits>
#include <cstdlib>
#include <cassert>
#include <numeric>
#include <math.h>
#include <random>

using namespace std;
  
#define rep(i,n) for(int i=0;i<(n);++i)
#define reps(i,n) for(int i=1;i<=(n);++i)
#define all(x) (x).begin(),(x).end()
#define setout(n,x) setw(n+1) << setfill(x)
#define Fixed fixed << setprecision(14)
#define int int64_t
using pii = pair<int,int>;
constexpr int INF  = 0x3f3f3f3f;
constexpr long long LINF = 0x3f3f3f3f3f3f3f3fLL;
constexpr int mod = 1e9+7; 

constexpr int dy[] = {1,0,-1,0,1,-1,-1,1};
constexpr int dx[] = {0,1,0,-1,1,1,-1,-1};
 
template <class A, class B> inline bool chmax(A &a, const B &b) { return b > a && (a = b, true); }
template <class A, class B> inline bool chmin(A &a, const B &b) { return b < a && (a = b, true); }
 
template <class T> using min_heap = priority_queue<T,vector<T>,greater<T> >;
template <class T> using max_heap = priority_queue<T>;

inline int gcd(int a, int b){ return b ? gcd(b,a % b) : a;}
inline int lcm(int a, int b){ return a / gcd(a,b) * b;}
inline int updiv(int a, int b){ return (a + b - 1) / b; }

signed main(void){
    cin.tie(nullptr);
    ios_base::sync_with_stdio(false);

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

    int maxv = 0,res = 0;
    vector<int> v(n);

    rep(i,n){
        int a;
        cin >> a >> v[i];
        chmax(maxv,a);
    }

    sort(all(v),greater<int>());
    for(int i = 0; i < n && h > 0 && v[i] > maxv; ++i){
        h -= v[i];
        ++res;
    }
    
    cout << res + updiv(max(0ll,h),maxv) << '\n';

    return 0;
}