#include<algorithm>
#include<iostream>
#include<vector>
using namespace std;
typedef long long lint;
typedef vector<int>vi;
typedef pair<int,int>pii;
#define rep(i,n)for(int i=0;i<(int)(n);++i)

const double ans1=-1.1638780202724224;
const double ans2=-1.3555525130426718;
const double ans4=-1.995873239222159;

const int DEBUG=0;

#if 0
int main(){
  double coef[5];
  rep(i,8) {
    double c;cin>>c;
    if(i==0)coef[0]+=c;
    else if(i==7)coef[1]+=c;
    else if(i==1||i==2||i==4)coef[2]+=c;
    else coef[3]+=c;
  }
  rep(i,8){
    double c;cin>>c;
    coef[4]+=c;
  }
  if(DEBUG){
    cerr<<"coef:";
    rep(i,5)cerr<<" "<<coef[i];
    cerr<<endl;
  }
  double ef=ans2/2*3;
  double gh=ans2/2-ans1;
  printf("E-F=%.15f\n",ef);
  printf("G-H=%.15f\n",gh);
  double ans;cin>>ans;
  if(DEBUG){
    cerr<<coef[0]<<"E+"<<coef[1]<<"F+"<<coef[2]<<"G+"<<coef[3]<<"H+"<<
      coef[4]<<"I="<<ans<<endl;
  }
  double tmp=ans;
  {
    tmp+=coef[1]*ef;
    coef[0]+=coef[1];
    coef[1]=0;
  }
  {
    tmp+=coef[3]*gh;
    coef[2]+=coef[3];
    coef[3]=0;
  }
  if(DEBUG){
    cerr<<coef[0]<<"E+"<<coef[1]<<"F+"<<coef[2]<<"G+"<<coef[3]<<"H+"<<
      coef[4]<<"I="<<tmp<<endl;
  }
  double egi=tmp/coef[0];
  printf("E+3G-4I=%.15f\n",egi);
}
#else
double ef=-2.033328769564008;
double gh=0.486101763751086;
double egi=-2.323933631643025;
int main(){
  double coef[5];
  rep(i,8) {
    double c;cin>>c;
    if(i==0)coef[0]+=c;
    else if(i==7)coef[1]+=c;
    else if(i==1||i==2||i==4)coef[2]+=c;
    else coef[3]+=c;
  }
  rep(i,8){
    double c;cin>>c;
    coef[4]+=c;
  }
  double ans=0;
  ans-=coef[1]*ef;
  ans-=coef[3]*gh;
  ans+=-coef[4]/4*egi;
  printf("%.15f\n",ans);
}
#endif