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