#include<bits/stdc++.h>
using namespace std;
#define int long long
const int N = 1010;
const int maxN = 1e6 + 10;
const int d[4][2] = {{0,1},{0,-1},{1,0},{-1,0}};
int t,m,n,a[N][N];
int b[maxN],ww[maxN],cnt = -1;
void dfs(int x,int y,int w,int len) {
	int sum = 0;
	for(int i = 0; i < 4; i++) {
		int sx = x + d[i][0],sy = y + d[i][1];
		if(sx >= 1 && sx <= n && sy >= 1 && sy <= m && a[sx][sy] > w) {
			len += 1;
			b[len] = a[sx][sy];
			dfs(sx,sy,a[sx][sy],len);
			len -= 1;
		} else {
			sum += 1;
		}
	}
	if(sum == 4) {
		if(len > cnt) {
			cnt = len;
			for(int i = 1;i <= cnt;++i){
				ww[i] = b[i];
			}
		} else if(len == cnt) {
			bool flag = false;
			for(int i = 1; i <= len; ++i) {
				if(b[i] < ww[i]) flag = true;
			}
			if(flag == true) {
				for(int i = 1; i <= len; ++i) {
					ww[i] = b[i];
				}
			}
		}
	}
	return;
}
int32_t main() {
	scanf("%lld",&t);
	while(t--) {
		cnt = 0;
		memset(b,0,sizeof(b));
		memset(ww,0,sizeof(ww));
		scanf("%lld %lld",&n,&m);
		for(int i = 1; i <= n; ++i) {
			for(int j = 1; j <= m; ++j) {
				scanf("%lld",&a[i]);
			}
		}
		for(int i = 1; i <= n;++i) {
			for(int j = 1; j <= m; ++j) {
				b[1] = a[i][j];
				dfs(i,j,a[i][j],1);
			}
		}
		printf("%lld\n",cnt);
		for(int i = 1;i <= cnt;++i){
			printf("%lld ",ww[i]);
		}
		printf("\n");
	}
	return 0;
}