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