#include<bits/stdc++.h>
#define ll long long
using namespace std;
long long read(){
	long long x=0,f=1;char ch=getchar();
	while(!isdigit(ch))
	{if(ch=='-') f=-1;ch=getchar();}
	while(isdigit(ch)){x=x*10+ch-48;ch=getchar();}
	return x*f;
}
void write(long long x){
    if(x<0) putchar('-'),x=-x;
    if(x>9) write(x/10);
    putchar(x%10+'0');
}
const int N=5010;
int T,n;
char a[N][N],b[N][N];
void solve(){
	int cnt=0;
	for(int i=1;i<=n;i++){
		for(int j=1;j<=i;j++){
			if(a[i][j]=='0'){
				b[i][j]='-';cnt++;continue;
			}
			if(j>1&&b[i][j-1]!='3'&&b[i-1][j-1]!='2'){
				b[i][j]='1';continue;
			}
			if(j<i&&b[i-1][j]!='2'){
				b[i][j]='3';continue;
			}
			b[i][j]='2';
		}
	}
	if(cnt!=n){
		printf("Impossible\n");return;
	}
	for(int i=1;i<=n;i++){
		for(int j=1;j<=i;j++){
			putchar(b[i][j]);
		}
		puts("");
	}
}
int main(){
	//freopen(".in","r",stdin);
	//freopen(".out","w",stdout);
	T=read();
	while(T--){
		n=read();
		for(int i=1;i<=n;i++){
			for(int j=1;j<=i;j++){
				cin>>a[i][j];
			}
		}
		solve();
	}
	return 0;
}