#include<cstdio>
using namespace std;
int main()
{
int s,n;
scanf("%d",&n);
if(n>=0&&n<=4)s=0;
else if(n>=5&&n<=8)s=1;
else if(n>=9&&n<=11)s=3;
else if(n>=12&&n<=13)s=6;
else if(n>=14&&n<=15)s=10;
else if(n==16)s=15;
else if(n>=17&&n<=18)s=21;
else if(n>=19&&n<=20)s=28;
else if(n==21)s=35;
else if(n>=22&&n<=23)s=30;
else if(n==24)s=27;
else s=12;
printf("%d\n",s);
return 0;
}