#include<stdio.h>
int main()
{
	int m,s,t,i,ans;
	scanf("%d %d %d",&m,&t,&s);
	if(t==0)
	printf("%d",m);
	else
	{
		if(s%t==0)
		{
		i=s/t;
	    ans=m-i;
		printf("%d",ans);	
		}
		else{
			i=s/t+1;
			ans=m-i;
			printf("%d",ans);
		}
	}
	return 0;
}