#include<bits/stdc++.h>
#include<atcoder/all>
#define chmin(x,y) (x) = min((x),(y))
#define chmax(x,y) (x) = max((x),(y))
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define vec vector
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define pb push_back 
#define eb emplace_back

using namespace std;
using namespace atcoder;
using ll = long long;
using ld = long double;
const ll mod = 998244353;
using mint = modint998244353;
const vector<int> dx = {1,0,-1,0}, dy = {0,1,0,-1};
// using Graph = vector<vector<pair<int,ll>>>;
using Graph = vector<vector<int>>;

int main(){
  // input
  int N, M;
  cin >> N >> M;
  vector<int> A(N),B(N),C(N);
  map<int,int> cnt;
  rep(i,N){
    cin >> A[i] >> B[i];
    C[i] = (M - A[i] + B[i]) / B[i];
    cnt[C[i]]++;
  }

  // solve
  int ans = 0, now = 0;
  for(auto[k,v] : cnt){
    now += v;
    chmax(ans,(now+k-1) / k);
  }

  // output
  cout << ans << endl;
}