#include<stdio.h>

void main () {
	int n;
	scanf("%d",&n);
	
	if(n%30==0){
		printf("%d",n/30);
	}else{
		printf("%d",n/30+1);
	}
}
/**************************************************************
	Problem: 1632
	User: admin
	Language: C
	Result: Accepted
	Time:13 ms
	Memory:1144 kb
****************************************************************/