#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  long long int a, b, c, x, y, z, ra = 0, rb = 0, rc = 0, ea = 0, eb = 0,
                                  ec = 0, t = 0;
  cin >> a >> b >> c >> x >> y >> z;
  if (a > x)
    ea = a - x;
  else
    ra = x - a;
  if (b > y)
    eb = b - y;
  else
    rb = y - b;
  if (c > z)
    ec = c - z;
  else
    rc = z - c;
  t += ea / 2;
  t += eb / 2;
  t += ec / 2;
  if (t >= (ra + rb + rc))
    cout << "Yes";
  else
    cout << "No";
  return 0;
}
