#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
#define MP(a,b) make_pair(a,b)
int main() {
	ios::sync_with_stdio ( false );
	int a, b, c;
	scanf ( "%d%d%d", &a, &b, &c );
	printf ( "%d", int ( a * 0.2 + b * 0.3 + c * 0.5 ) );
	return 0;
}