#include <bits/stdc++.h>
using namespace std;
const long long MAXN = 1e3 + 7;
const long long MOD = 1e9 + 7;
int main() {
  int a, b, c;
  cin >> a >> b >> c;
  int x, y, z;
  cin >> x >> y >> z;
  if (a >= x && b >= y && c >= z)
    cout << "Yes" << endl;
  else if ((a <= x && b <= y && c <= z) && (a < x || b < y || c < z))
    cout << "No" << endl;
  else {
    int mor = max(0, a - x) / 2 + max(0, b - y) / 2 + max(0, c - z) / 2;
    int les = max(0, x - a) + max(0, y - b) + max(0, z - c);
    if (les <= mor)
      cout << "Yes" << endl;
    else
      cout << "No" << endl;
  }
  return 0;
}
