#include <bits/stdc++.h>
using namespace std;
int main() {
  int a[3][3];
  while (cin >> a[0][0]) {
    int r = 0, flag = 1;
    for (int i = 1; i < 3; i++) cin >> a[0][i];
    for (int j = 0; j < 3; j++) {
      cin >> a[1][j];
      a[2][j] = a[0][j] - a[1][j];
      if (a[2][j] > 0) {
        r += a[2][j] / 2;
        a[0][j] -= a[2][j] / 2 * 2;
      }
    }
    for (int j = 0; j < 3; j++) {
      if (a[2][j] < 0) {
        int t = r + a[2][j];
        if (t < 0) {
          flag = 0;
          break;
        } else {
          r = t;
        }
      }
    }
    if (flag)
      cout << "Yes\n";
    else
      cout << "No\n";
  }
}
