# include <bits/stdc++.h>
using namespace std;
using ll=long long;
using Hash=pair<int,int>;
constexpr int p1=1e9+7,p2=1e9+9,Base=998244353;
char _s[3000010],*s[1000010];
bool vis[1000010];
Hash pw[1000010],_s1[3000010],*s1[1000010],_s2[3000010],*s2[1000010];
inline Hash operator+(const Hash &x,const Hash &y){return {(x.first+y.first)%p1,(x.second+y.second)%p2};}
inline Hash operator-(const Hash &x,const Hash &y){return {(x.first+p1-y.first)%p1,(x.second+p2-y.second)%p2};}
inline Hash operator*(const Hash &x,const Hash &y){return {(ll)x.first*y.first%p1,(ll)x.second*y.second%p2};}
int main()
{
	int T,n,m;
	cin>>T;
	pw[0]={1,1};
	for(int i=1;i<=1000000;i++) pw[i]=pw[i-1]*Hash{Base,Base};
	while(T--)
	{
		int ans=0;
		scanf("%d%d",&n,&m);
		auto Id=[&](int x,int y){return (x-1)*m+y;};
		for(int i=0,j=0;i<=n;i++,j+=m+1) s[i]=_s+j,s1[i]=_s1+j;
		for(int i=1,j=0;i<=n+1;i++,j+=m+1) s2[i]=_s2+j;
		for(int i=1;i<=n;i++) scanf("%s",s[i]+1);
		int x1=1,x2=n,y1=1,y2=m;
		for(int j=1;j<=m;j++)
		{
			for(int i=1;i<=n;i++) s1[i][j]=s1[i-1][j]*Hash{Base,Base}+Hash{s[i][j],s[i][j]};
			for(int i=n;i;i--) s2[i][j]=s2[i+1][j]*Hash{Base,Base}+Hash{s[i][j],s[i][j]};
		}
		auto chk1=[&](int x1,int x2)
		{
			if(x1>x2) return false;
			int L=(x2-x1+1)/2;
			for(int i=1;i<=m;i++)
				if(s1[x1+L-1][i]-pw[L]*s1[x1-1][i]!=s2[x2-L+1][i]-pw[L]*s2[x2+1][i])
					return false;
			return true;
		};
		for(int i=2,j=n-1;i<=x2 || j>=x1;cout<<i<<" , "<<j<<endl,i+=2,j-=2)
			if(chk1(x1,i)) x1=(x1+i+1)/2,i=x1-1,j=x2+1;
			else if(chk1(j,x2)) x2=(x2+j-1)/2,i=x1-1,j=x2+1;
		for(int i=1;i<=n;i++)
		{
			for(int j=1;j<=m;j++) s1[i][j]=s1[i][j-1]*Hash{Base,Base}+Hash{s[i][j],s[i][j]};
			for(int j=m;j;j--) s2[i][j]=s2[i][j+1]*Hash{Base,Base}+Hash{s[i][j],s[i][j]};
		}
		auto chk2=[&](int y1,int y2)
		{
			if(y1>y2) return false;
			int L=(y2-y1+1)/2;
			for(int i=x1;i<=x2;i++)
				if(s1[i][y1+L-1]-pw[L]*s1[i][y1-1]!=s2[i][y2-L+1]-pw[L]*s2[i][y2+1])
					return false;
			return true;
		};
		for(int i=2,j=m-1;i<=y2 || j>=y1;i+=2,j-=2)
			if(chk2(y1,i)) y1=(y1+i+1)/2,i=y1-1,j=y2+1;
			else if(chk2(j,y2)) y2=(y2+j-1)/2,i=y1-1,j=y2+1;
		auto dfs=[&](auto dfs,int x,int y)->void
		{
			if(x<x1 || x>x2 || y<y1 || y>y2 || s[x][y]=='1' || vis[Id(x,y)]) return;
			vis[Id(x,y)]=1;
			dfs(dfs,x-1,y);dfs(dfs,x+1,y);
			dfs(dfs,x,y-1);dfs(dfs,x,y+1);
		};
		for(int i=x1;i<=x2;i++)
			for(int j=y1;j<=y2;j++)
				if(s[i][j]=='0' && !vis[Id(i,j)])
					ans++,dfs(dfs,i,j);
		printf("%d\n",ans);
		memset(vis+1,0,sizeof(bool)*n*m);
		for(int i=1;i<=n;i++)
		{
			memset(s[i]+1,0,sizeof(char)*m);
			memset(s1[i]+1,0,sizeof(Hash)*m);
			memset(s2[i]+1,0,sizeof(Hash)*m);
		}
	}
	return 0;
}