#include<iostream>
using namespace std;
int main(){
	int m,n;
	cin>>m>>n;
	int degrees=(n-m)*30;
	cout<<degrees<<endl;
	return 0;
}
/**************************************************************
	Problem: 1320
	User: linyuhang
	Language: C++
	Result: Accepted
	Time:6 ms
	Memory:2072 kb
****************************************************************/