#include <stdio.h>
long g(long k) {
if (k <= 1) return k;
return (2002 * g(k - 1) + 2003 * g(k - 2)) % 2005;
}
int main() {
long n;
scanf("%ld", &n);
printf("%ld\n", g(n));
return 0;
输入:2005
输出: