#include <bits/stdc++.h>
using namespace std;
#define lll i << 1
#define rrr i << 1 | 1




      
    const int N=2e5+6;

int ma,mi;
int  n,m,a[N],b[N],dd[N];
int ans=0;

void solve()
{
	string s,s2;
	int res=0,q,re;
	ans=0;
	cin>>n>>m>>re>>q;
	for(int i=1;i<=n;i++)
		cin>>a[i];
	for(int j=1;j<=m;j++)
		cin>>b[j];
	sort(a+1,a+n+1);
	sort(b+1,b+m+1);
	b[++m]=q+1;
	int j=1;
	for(int i=0;i<=m;i++)
	{
		for(;j<=n;)
		{
			map<int,int> mp;
			int k=j,l=b[i],tt=0;
			if(b[i]<a[j]&&b[i+1]>a[j])
			{
				for(k=j;k<=n;k++)
				{
					if(b[i]<a[k]&&b[i+1]>a[k])
					{
						if(l>=a[k])
							continue;
						tt++;
						int r=min(b[i+1]-1,a[k]+re-1);
						
						int yy=r-re+1;
						
                        int mm=l-yy+1;
                        
						if(yy>l)
						{
							mp[tt]+=yy-l-1;
							if(mp[tt]==0)
								mp.erase(tt);
						}
						else
						{
							for (auto it = mp.rbegin(); it != mp.rend(); it++)
							{
							    auto &[x,y]=*it;
							    if(y<=mm)
							    {
							    	mm-=y;
							    	y=0;
							    	mp.erase(x);
									if(mp.size()==0)
										break;	
								}
								else
								{
									y-=mm;	
									mm=0;
								}
							}
						}
						if(mm>0)
						{
                            cout<<-1<<"\n";
							return ;
                        }
						l=r;
					}
					else
						break;
						
				}
				int rer=b[i];
				for(int qw=ans+1;qw<=ans+tt;qw++)
				{
					dd[qw]=rer+mp[qw-ans]+1;
                    //cout<<qw<<" "<<j<<" "<<b[i]<<" "<<mp[qw-ans]<<" "<<rer<<" "<<dd[qw]<<"\n";
					rer=dd[qw]+re-1;			
				}
				j=k;
			}
			else
				break;
			ans+=tt;
			
		}
	}
	cout<<ans<<"\n";
	for(int i=1;i<=ans;i++)
		cout<<dd[i]<<" ";
	for(int i=1;i<=max(n,m,ans);i++)
	{
		a[i]=b[i]=dd[i]=0;
	}
	cout<<"\n";

}

signed main()
{
	std::ios::sync_with_stdio(false);//取消cin与stdin同步,加速读入 
	cin.tie(0);cout.tie(0);
 	int t;
 	t=1;
 	
	cin>>t;
	while(t--)
	{
		solve();
	}
	
    return 0;
}

answer.code: In function ‘void solve()’:
answer.code:61:67: warning: structured bindings only available with ‘-std=c++17’ or ‘-std=gnu++17’ [-Wc++17-extensions]
   61 |                                                             auto &[x,y]=*it;
      |                                                                   ^
In file included from /usr/include/c++/13/algorithm:60,
                 from /usr/include/x86_64-linux-gnu/c++/13/bits/stdc++.h:51,
                 from answer.code:1:
/usr/include/c++/13/bits/stl_algobase.h: In instantiation of ‘constexpr const _Tp& std::max(const _Tp&, const _Tp&, _Compare) [with _Tp = int; _Compare = int]’:
answer.code:106:20:   required from here
/usr/include/c++/13/bits/stl_algobase.h:306:17: error: ‘__comp’ cannot be used as a function
  306 |       if (__comp(__a, __b))
      |           ~~~~~~^~~~~~~~~~