#include<stdio.h>
int main(){
	int L, R, C, i, temp, ans = 1000, bill = 1000;
	scanf("%d%d%d", &L, &R, &C);
	temp = (L % bill) * (C % bill) % bill;
	for(i = L;i <= R; ++i){
		if(ans > temp){
			ans = temp;
		}
		temp = (temp + C) % bill;
		if(ans == 0){
			break;
		}
	}
	printf("%d\n", ans);
}