#include <bits/stdc++.h>
using namespace std;
int main() {
  int a, b, c;
  cin >> a >> b >> c;
  int x, y, z;
  cin >> x >> y >> z;
  a -= x;
  b -= y;
  c -= z;
  if (a >= 0 && b >= 0 && c >= 0) {
    cout << "Yes";
    return 0;
  }
  if (a >= 0) a /= 2;
  if (b >= 0) b /= 2;
  if (c >= 0) c /= 2;
  int sum = 0, sum2 = 0;
  if (a >= 0)
    sum += a;
  else
    sum2 += a;
  if (b >= 0)
    sum += b;
  else
    sum2 += b;
  if (c >= 0)
    sum += c;
  else
    sum2 += c;
  if (sum + sum2 >= 0)
    cout << "Yes";
  else
    cout << "No";
  return 0;
}
