#include <bits/stdc++.h>
using namespace std;
int a[100100],b[100010],n,k;
int check(int c){
int ans=0;
for(int i=1;i<=n;++i){
ans+=a[i]/c*b[i]/c;
}
return ans;
}
int main() {
cin>>n>>k;
for(int i=1;i<=n;++i){
cin>>a[i]>>b[i];
}
int l=1,r=100000;
while(l<r){
int mid=(l+r+1)>>1;
if(check(mid)>=k)l=mid;
else r=mid-1;
}
cout<<l<<endl;
return 0;
}