#include <bits/stdc++.h>
using namespace std;
const long long int M = 1e9 + 7;
int main() {
  long long int a, b, c, x, y, z, ans1 = 0, ans2 = 0;
  cin >> a >> b >> c >> x >> y >> z;
  if (a >= x)
    ans1 += (a - x) / 2;
  else
    ans2 += a - x;
  a = b;
  x = y;
  if (a >= x)
    ans1 += (a - x) / 2;
  else
    ans2 += a - x;
  a = c;
  x = z;
  if (a >= x)
    ans1 += (a - x) / 2;
  else
    ans2 += a - x;
  ans1 = ans1 + ans2;
  if (ans1 >= 0)
    cout << "Yes\n";
  else
    cout << "No\n";
  return 0;
}
