#include <bits/stdc++.h>
const int INF = 1 << 30;
inline int read() {
  int x = 0;
  bool f = false;
  char ch = getchar();
  while (ch < '0' || ch > '9') {
    if (ch == '-') f = true;
    ch = getchar();
  }
  while (ch >= '0' && ch <= '9') {
    x = (x << 1) + (x << 3) + ch - '0';
    ch = getchar();
  }
  if (f) return -x;
  return x;
}
const int D = 50;
int a, b, c, x, y, z;
int rem, ned;
int main() {
  a = read();
  b = read();
  c = read();
  x = read();
  y = read();
  z = read();
  if (a > x)
    rem += (a - x) / 2;
  else
    ned += x - a;
  if (b > y)
    rem += (b - y) / 2;
  else
    ned += y - b;
  if (c > z)
    rem += (c - z) / 2;
  else
    ned += z - c;
  if (rem >= ned)
    printf("Yes");
  else
    printf("No");
  return 0;
}
