#include<bits/stdc++.h> using namespace std; int main() { int a,b; cin>>a>>b; cout<<(b-a)*30; return 0; }

#include<bits/stdc++.h>
using namespace std;
int main(){

	int m,n;
	cin>>m>>n;
	cout<<(n-m)*30<<endl;
	


	return 0;
}

#include<iostream>
using namespace std;
int main(){
int a,b;
cin>>a>>b;
cout<<(b-a)*30;
return 0;
}