#include <bits/stdc++.h>
using namespace std;
int main() {
  int a, b, c, d, e, f, g = 0, h = 0, i = 0, j, k, l, p = 0;
  cin >> a >> b >> c >> d >> e >> f;
  g = a - d;
  h = b - e;
  i = c - f;
  if (g > 0) {
    j = g / 2;
  } else {
    j = 0;
  }
  if (h > 0) {
    k = h / 2;
  } else {
    k = 0;
  }
  if (i > 0) {
    l = i / 2;
  } else {
    l = 0;
  }
  if (g >= 0) {
    p = p + j;
  } else {
    p = p + g;
  };
  if (h >= 0) {
    p = p + k;
  } else {
    p = p + h;
  }
  if (i >= 0) {
    p = p + l;
  } else {
    p = p + i;
  }
  if (p >= 0) {
    cout << "Yes";
  } else {
    cout << "No";
  }
  return 0;
}
