#include <bits/stdc++.h>
using namespace std;
const int c = 1E9 + 7;
int main() {
  int cnt = 0;
  int a, b, c, a0, b0, c0;
  cin >> a >> b >> c >> a0 >> b0 >> c0;
  int sum = 0;
  if (a - a0 > 0) cnt += (a - a0) / 2;
  if (b - b0 > 0) cnt += (b - b0) / 2;
  if (c - c0 > 0) cnt += (c - c0) / 2;
  if (a - a0 < 0) cnt += a - a0;
  if (b - b0 < 0) cnt += b - b0;
  if (c - c0 < 0) cnt += c - c0;
  if (cnt >= 0)
    cout << "Yes";
  else
    cout << "No";
  return 0;
}
