此算法正确吗，样例能过

#include<bits/stdc++.h>
#define int long long
#define fi first
#define se second
#define PII pair<int,int>
using namespace std;
int n,m;
PII a[100005];
int ms=1e18,mp=1e18;//min single  min pair
signed main(){
    cin>>n>>m;
    for(int i=1;i<=n;i++){
        cin>>a[i].fi>>a[i].se;
        ms=min(ms,a[i].fi);
        mp=min(mp,a[i].fi+a[i].se);
    }
    int ans=0;
    while(m>=mp){
        ans+=2;
        m-=mp;
    }
    if(m>=ms) ans++;
    cout<<ans;
}