parfum

#include <iostream>
#define ULL unsigned long long int
using namespace std;
int n,x,z,t;
struct floare
{
    int c,d;
}a[100005];

int solve()
{
    int st=1,dr=t,tmax=0;
    while(st<=dr)
    {
        ULL flori=0;
        int mij=(st+dr)/2;
        for(int i=1;i<=n;++i)
            flori+=1ULL*a[i].c*min(z/mij,a[i].d/mij);
        if(flori>=1ULL*x)
            tmax=max(mij,tmax),st=mij+1;
        else
            dr=mij-1;
    }
    return tmax;
}

int main()
{
    cin>>n>>x>>z;
    for(int i=1;i<=n;++i)
        cin>>a[i].c>>a[i].d,t=max(t,a[i].d);
    cout<<solve()<<'\n';
    return 0;
}