#include <bits/stdc++.h>
using namespace std;
void Solve() {
  vector<int> a(3);
  vector<int> b(3);
  for (auto& x : a) cin >> x;
  for (auto& x : b) cin >> x;
  vector<int> s(3);
  vector<int> d(3);
  for (int i = 0; i < 3; i++) {
    if (a[i] > b[i]) {
      s[i] = a[i] - b[i];
      d[i] = 0;
    } else {
      d[i] = b[i] - a[i];
      s[i] = 0;
    }
  }
  for (int i = 0; i < 3; i++) {
    for (int j = 0; j < 3 && d[i]; j++) {
      if (s[j] / 2 >= d[i]) {
        s[j] -= 2 * d[i];
        d[i] = 0;
      } else {
        int x = s[j] / 2;
        s[j] -= x * 2;
        d[i] -= x;
      }
    }
    if (d[i] != 0) {
      cout << "No";
      return;
    }
  }
  cout << "Yes";
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  {
    Solve();
    cout << '\n';
  }
  return 0;
}
