#include <stdio.h>

long gcd(long x, long y)
{
    long r;
    if (y > x) {
        r = x;
        x = y;
        y = r;
    }
    while (y > 0) {
        r = x % y;
        x = y;
        y = r;
    }
    return x;
}

int main(void)
{
    long N;
    scanf("%ld", &N);
    printf("%ld", gcd(N, (N - 1) * N / 2));
    return 0;
}