#include <bits/stdc++.h>
using namespace std;
int main() {
  int arr[7];
  int a, b, c, x, y, z;
  int sp = 0, need = 0;
  int i;
  for (i = 1; i <= 6; i++) {
    cin >> arr[i];
  }
  for (i = 1; i <= 3; i++) {
    a = arr[i];
    x = arr[i + 3];
    if (a >= x) {
      sp += (a - x) / 2;
    } else {
      need += x - a;
    }
  }
  if (sp >= need)
    cout << "Yes";
  else
    cout << "No";
  return 0;
}
