#include <bits/stdc++.h>
using namespace std;
void yala_bena() {
  cin.tie(0);
  std::ios::sync_with_stdio(false);
}
int main() {
  yala_bena();
  int a, b, c, x, y, z, r1 = 0, r2 = 0, r3 = 0, need = 0, test = 0;
  cin >> a >> b >> c >> x >> y >> z;
  if (x <= a) {
    test++;
    r1 += (a - x);
  } else
    need += (x - a);
  if (y <= b) {
    test++;
    r2 += (b - y);
  } else
    need += (y - b);
  if (z <= c) {
    test++;
    r3 += (c - z);
  } else
    need += (z - c);
  need -= r3 / 2;
  need -= r2 / 2;
  need -= r1 / 2;
  if (test == 3 || need <= 0)
    cout << "Yes" << endl;
  else {
    cout << "No" << endl;
  }
}
