#include <stdio.h>

int main()
{
	int m,s,t,a=0;
	scanf("%d %d %d",&m,&t,&s);
	if (t==0)
	{
		printf("%d",a);
		return 0;
	}
	else
	{
	if (s%t==0)
	printf("%d\n",m-s/t);
	else 
	printf("%d\n",m-s/t-1);
	return 0;
	}
}