#include<stdio.h> int main() { int a = 0; int b = 0; int c = 0; int d = 0; scanf("%d%d%d%d", &a, &b, &c, &d); float sum = a * 0.2 + b * 0.1 + c * 0.2 + d * 0.5; printf("%.1f", sum); return 0; }