#include<bits/stdc++.h>
using namespace std;
int main(){
	int m=0,n=0;
	cin>>m>>n;
	cout<<(360/12)*(n-m);
}
 
/**************************************************************
	Problem: 1320
	User: lvrenxiang
	Language: C++
	Result: Accepted
	Time:7 ms
	Memory:2072 kb
****************************************************************/