2869

#pragma warning (disable: 4996)
#include <stdio.h>
#include <string.h>
int main() {
	int A, B, V;
	int day;
	scanf("%d %d %d", &A, &B, &V);
	day = (V - B - 1) / (A - B) + 1;
	printf("%d",day);

	return 0;
}