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