#include<bits/stdc++.h>
using namespace std;
int a[200000+5];
int T,n,m;
int get_num(int x,int y)
{
	return (x-1)*m+y;	
}
int hu[200000+5];//1:down 2:up 3:right 4:left
int dp[200000+5];
int dir[4][2]={0,1,0,-1,1,0,-1,0};//
int fun(int x,int y)
{
	if(dp[get_num(x,y)])
		return dp[get_num(x,y)];
	int l[4]={0};
	for(int i=0;i<4;i++)
	{
		if(x+dir[i][0]>0&&x+dir[i][0]<=n&&y+dir[i][1]>0&&y+dir[i][1]<=m&&a[get_num(x,y)]<a[get_num(x+dir[i][0],y+dir[i][1])])
		{
			l[i]=fun(x+dir[i][0],y+dir[i][1]);
		}
	}
	int maxx=max({l[0],l[1],l[2],l[3]});
	if(maxx==0)
	{
		hu[get_num(x,y)]=0; 
		return dp[get_num(x,y)]=1;	
	}
	int cj1=INT_MAX,cj2;
	for(int i=0;i<=3;i++)
	{
		if(l[i]==maxx)
		{
			if(a[get_num(x+dir[i][0],y+dir[i][1])]<cj1)
			{
				cj1=a[get_num(x+dir[i][0],y+dir[i][1])];
				cj2=i+1;
			}
		}
	}
	hu[get_num(x,y)]=cj2;	 
	return dp[get_num(x,y)]=maxx+1;
}
void DFS(int x,int y)
{
	printf("%d ",a[get_num(x,y)]);
	if(hu[get_num(x,y)]==0)
		printf("\n");
	else
		DFS(x+dir[hu[get_num(x,y)]-1][0],y+dir[hu[get_num(x,y)]-1][1]);
}
int main()
{
	scanf("%d",&T);
	while(T--)
	{
		memset(dp,0,sizeof(dp));
		memset(hu,0,sizeof(hu));
		scanf("%d %d",&n,&m);
		for(int i=1;i<=n;i++)
			for(int j=1;j<=m;j++)
				scanf("%d",&a[get_num(i,j)]);
		int maxx=0,fx,fy,c=INT_MAX;
		for(int i=1;i<=n;i++)
			for(int j=1;j<=m;j++)
			{
				if(fun(i,j)>=maxx)
				{
					maxx=fun(i,j);
					if(a[get_num(i,j)]<c)
					{
						fx=i,fy=j,c=a[get_num(i,j)];
					}
				}
			}
		printf("%d\n",maxx);
		DFS(fx,fy);
	}
	return 0;
}