#include<stdio.h>

int main()
{
	int m, t, s;
	scanf("%d %d %d", &m, &t, &s);
	if (t != 0)
	{
		int ate = s / t;
		int eatting = s % t == 0 ? 0 : 1;
		int num = m - ate - eatting;
		if (num > 0)
		{
			printf("%d", num);
		}
		else
		{
			printf("%d", 0);
		}
	}
	else
	{
		printf("%d", m);
	}
	return 0;
}