#include <bits/stdc++.h>
using namespace std;
int main() {
  long long a, b, c, x, y, z, k;
  cin >> a >> b >> c >> x >> y >> z;
  k = x - min(x, a) + y - min(b, y) + z - min(z, c);
  a = (a >= x) * (a - x);
  b = (b >= y) * (b - y);
  c = (c >= z) * (c - z);
  if (k > (a / 2) + (b / 2) + (c / 2))
    cout << "No";
  else
    cout << "Yes";
  return 0;
}
