#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
using namespace std;
const int INF = 1e9, MOD = INF - 1755647;
int gcd(int a, int b) { return (b ? gcd(b, a % b) : a); }
int power(int a, int b) {
  return (!b ? 1 : power(a, b / 2) * power(a, b / 2) * (b % 2 ? a : 1));
}
int mod(int a) { return (a % MOD + MOD) % MOD; }
const int N = 2e5 + 20;
struct node {
  int val = 0;
  bool marked = false;
  vector<int> adj;
};
int a[N];
node g[N];
set<int> ans;
void run(int src) {
  g[src].marked = true;
  queue<int> q;
  q.push(src);
  while (!q.empty()) {
    int v = q.front();
    q.pop();
    g[v].val++;
    ans.insert(v);
    for (int u : g[v].adj) {
      g[u].val++;
      if (!g[u].marked && g[u].val == a[u]) q.push(u);
    }
  }
}
int32_t main() {
  ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
  int n, m;
  cin >> n >> m;
  for (int i = 0; i < m; i++) {
    int v, u;
    cin >> v >> u;
    g[v].adj.push_back(u);
    g[u].adj.push_back(v);
  }
  for (int i = 1; i <= n; i++) cin >> a[i];
  for (int i = 1; i <= n; i++)
    if (g[i].val == a[i]) run(i);
  cout << ans.size() << "\n";
  for (int v : ans) cout << v << " ";
  cout << "\n";
  return 0;
}
