#include <cstdio>

using namespace std;

int main()
{
    long long int p;
    freopen("fact.in", "r", stdin);
    freopen("fact.out", "w", stdout);
    scanf("%lld",&p);
    if(p == 0){
        printf("1\n");
    }else{
        if((4*p + 1) % 5 == 0){
            printf("%lld",4*p+1 - p/2);
        }else if((4*p + 2)% 5 == 0){
            printf("%lld",4*p+2 - p/2);
        }else if((4*p + 3)% 5 == 0){
            printf("%lld",4*p+3 - p/2);
        }else if((4*p + 4)% 5 == 0){
            printf("%lld",4*p+4 - p/2);
        }else if((4*p + 5)% 5 == 0){
            printf("%lld",4*p+5 - p/2);
        }
    }
    return 0;
}