题解

#include <bits/stdc++.h>
using namespace std;
int main()
{
int n,x,y;
cin>>n>>x>>y;
if(y%x==0)
{
if(n-y/x<=0)
{
cout<<"0";
}
else
{
cout<<n-y/x;
}

}
else if(n-((y/x)+1)<=0)
{
    cout<<"0";
}
else
{
    cout<<n-((y/x)+1);
}
return 0;

}