#include <bits/stdc++.h>
using namespace std;
int main() {
  long long int A, a, B, b, C, c, aa = 0, bb = 0, cc = 0;
  scanf("%lld%lld%lld", &A, &B, &C);
  scanf("%lld%lld%lld", &a, &b, &c);
  if (A >= a) {
    aa = (A - a) / 2;
  } else
    aa = A - a;
  if (B >= b) {
    bb = (B - b) / 2;
  } else
    bb = B - b;
  if (C >= c) {
    cc = (C - c) / 2;
  } else
    cc = C - c;
  if ((aa + bb + cc) >= 0)
    printf("Yes\n");
  else
    printf("No\n");
  return 0;
}
