#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n,x,y;
    cin>>n>>x>>y;
    int z=y%x;
    int a=y/x;
    if(z!=0)
    {
        a=a+1;
    }
    cout<<n-a;
	return 0; 
}

#include<bits/stdc++.h> using namespace std; int main() { int x,y,n; cin>>n>>x>>y; int a=(y+x-1)/x; int b=n-a; if(b<=0) { b=0; } cout<<b; }