codeforces -242-D

/* Whenever no of edges is <= 1e6 then if we insert all nodes in a set and each node is accessed exactly once then the loop below runs exactly o(2*m) times ... because all edges are accessed by two of it's connecting nodes exactly two times...... */

int main()
{
    booster()
    ///read("input.txt");

    int n,m;cin>>n>>m;
    for(int i = 1;i<=m;i++)
    {
        int a,b;
        cin>>a>>b;
        v[a].pb(b);
        v[b].pb(a);
    }
    set<int>s;
    vi ans;
    for(int i = 1;i<=n;i++)
    {
        cin>>arr[i];
        if(arr[i]==0)s.insert(i);
    }

    while(!s.empty())
    {
        int x = *s.begin();
        s.erase(x);
        if(cnt[x]!=arr[x])continue;
        cnt[x]++;
        ans.pb(x);
        for(auto it : v[x])
        {
            cnt[it]++;
            if(arr[it]==cnt[it])s.insert(it);
        }
    }

    cout<<ans.size()<<endl;

    for(auto it : ans)cout<<it<<" ";


    return 0;
}