#include <bits/stdc++.h>
using namespace std;
pair<int, pair<int, int> > p[4];
int a[5];
int main(int argc, char** argv) {
  for (int i = 0; i < 3; i++) {
    scanf("%d", &p[i].second.first);
  }
  for (int i = 0; i < 3; i++) {
    scanf("%d", &p[i].second.second);
  }
  for (int i = 0; i < 3; i++) {
    p[i].first = p[i].second.first - p[i].second.second;
  }
  sort(p, p + 3);
  for (int i = 0; i < 3; i++) {
    if (p[i].first >= 0)
      a[i] = p[i].first / 2;
    else
      a[i] = p[i].first;
  }
  if (a[0] + a[1] + a[2] >= 0)
    printf("YES");
  else
    printf("NO");
  return 0;
}
