#include <stdio.h>
 int main ()
 {
 	int n,m;
 	scanf("%d",&n);
 	m=3*n;
 	printf("%d",m);
 	return 0;
 }
/**************************************************************
	Problem: 1596
	User: admin
	Language: C
	Result: Accepted
	Time:11 ms
	Memory:1144 kb
****************************************************************/