#include <bits/stdc++.h>
using namespace std;
long long mod = 1e9 + 7;
long long inf = 4e18;
const long long N = 5e5 + 5;
signed main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  long long tt = 1;
  while (tt--) {
    long long arr[3], brr[3], crr[3];
    for (long long i = 0; i < 3; ++i) cin >> arr[i];
    for (long long i = 0; i < 3; ++i) cin >> brr[i];
    for (long long i = 0; i < 3; ++i) crr[i] = arr[i] - brr[i];
    long long xxx = 0, yyy = 0;
    for (long long i = 0; i < 3; ++i) {
      if (crr[i] < 0)
        xxx += abs(crr[i]);
      else
        yyy += (crr[i] / 2);
    }
    if (yyy >= xxx) {
      cout << "Yes";
    } else
      cout << "No";
  }
  return 0;
}
