#include <bits/stdc++.h>
using namespace std;
int gcd(int a, int b) {
  if (b == 0) return a;
  return gcd(b, a % b);
}
long long int power(long long int a, long long int b) {
  long long int res = 1;
  while (b) {
    if (b & 1) {
      res = (res * a) % 1000000007;
    }
    a = (a * a) % 1000000007;
    b >>= 1;
  }
  return res;
}
long long int expo(long long int a, long long int b) {
  long long int res = 1;
  while (b) {
    if (b & 1) {
      res = (res * a);
    }
    a = (a * a);
    b >>= 1;
  }
  return res;
}
void solve() {
  int a, b, c, x, y, z;
  cin >> a >> b >> c >> x >> y >> z;
  int da = a - x, db = b - y, dc = c - z;
  if (da >= 0 && db >= 0 && dc >= 0)
    cout << "Yes\n";
  else {
    int create = 0;
    if (da > 0) create += da / 2;
    if (db > 0) create += db / 2;
    if (dc > 0) create += dc / 2;
    if (da < 0) create += da;
    if (db < 0) create += db;
    if (dc < 0) create += dc;
    if (create >= 0)
      cout << "Yes\n";
    else
      cout << "No\n";
  }
}
int main() {
  std::ios::sync_with_stdio(false);
  int t;
  t = 1;
  while (t--) {
    solve();
  }
  return 0;
}
