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