#include <bits/stdc++.h>
using namespace std;
int a, b, c, a2, b2, c2, suma;
int main() {
  cin >> a >> b >> c;
  cin >> a2 >> b2 >> c2;
  if (a > a2) suma += (a - a2) / 2;
  if (a < a2) suma += a - a2;
  if (b > b2) suma += (b - b2) / 2;
  if (b < b2) suma += b - b2;
  if (c > c2) suma += (c - c2) / 2;
  if (c < c2) suma += c - c2;
  if (suma >= 0)
    cout << "Yes";
  else
    cout << "No";
  return 0;
}
