#include<iostream> // cin\cout\endl #include<cstdio> //scanf()\printf() #include<cstring> // strcpy()\strcat()\strcmp()\strlen()\memset() #include<cmath> //sqrt()\pow()\abs()\ceil()\floor()\max()\min() using namespace std; int main(){ int n,x,y,a; cin>>n>>x>>y; a=n-x*y; if(a<=0){ cout<<0; } else if(y%x>0){ a=y/x+1; cout<<n-a; } else if(x<=y){ cout<<n-1; } return 0; }