#include <bits/stdc++.h>
using namespace std;
const int INF = 0x3f3f3f3f;
int main() {
  int a[5], b[5], sum = 0;
  for (int i = 1; i <= 3; i++) cin >> a[i];
  for (int i = 1; i <= 3; i++) cin >> b[i];
  for (int i = 1; i <= 3; i++) {
    if (a[i] - b[i] < 0)
      sum += abs(a[i] - b[i]);
    else
      sum -= (a[i] - b[i]) / 2;
  }
  if (sum > 0)
    cout << "No" << endl;
  else
    cout << "Yes" << endl;
  return 0;
}
