#include <bits/stdc++.h>
using namespace std;
int main() {
  int a, b, c;
  cin >> a >> b >> c;
  int a1, b1, c1;
  cin >> a1 >> b1 >> c1;
  int need = 0;
  int have = 0;
  if (a < a1) {
    need += a1 - a;
  } else
    have += (a - a1) / 2;
  if (b < b1) {
    need += b1 - b;
  } else
    have += (b - b1) / 2;
  if (c < c1) {
    need += c1 - c;
  } else
    have += (c - c1) / 2;
  if (have >= need)
    cout << "Yes";
  else
    cout << "No";
  return 0;
}
