#include<cstdio>

int main()
{
    //freopen("A.in","r",stdin);
    //freopen("A.out","w",stdout);

    int n = 0;
    long long sum = 0;

    scanf("%d",&n);

    for(int i = 1; i <=  n; ++i)
    {
        sum += i;
    }

    if((sum & 1) == 0)
    {
        printf("15\n");
    }
    else
    {
        printf("16\n");
    }

    return 0;
}