#include <bits/stdc++.h>
template <typename T>
inline void read(T &x) {
  char c;
  bool nega = 0;
  while ((!isdigit(c = getchar())) && (c != '-'))
    ;
  if (c == '-') {
    nega = 1;
    c = getchar();
  }
  x = c - 48;
  while (isdigit(c = getchar())) x = x * 10 + c - 48;
  if (nega) x = -x;
}
template <typename T>
inline void writep(T x) {
  if (x > 9) writep(x / 10);
  putchar(x % 10 + 48);
}
template <typename T>
inline void write(T x) {
  if (x < 0) {
    putchar('-');
    x = -x;
  }
  writep(x);
}
template <typename T>
inline void writeln(T x) {
  write(x);
  putchar('\n');
}
int a, b, c;
int x, y, z;
int main() {
  read(a);
  read(b);
  read(c);
  read(x);
  read(y);
  read(z);
  int temp = 0;
  if (a >= x)
    temp += (a - x) / 2;
  else
    temp -= x - a;
  if (b >= y)
    temp += (b - y) / 2;
  else
    temp -= y - b;
  if (c >= z)
    temp += (c - z) / 2;
  else
    temp -= z - c;
  if (temp >= 0)
    puts("Yes");
  else
    puts("No");
}
