#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define MAXN 200010
inline ll read(){
	ll x=0,f=1;
	char c=getchar();
	while(c<'0'||c>'9'){
		if(c=='-')f=-1;
		c=getchar();
	}
	while(c>='0'&&c<='9'){
		x=x*10+c-'0';
		c=getchar();
	}
	return x*f;
}
ll T,n,pd,a,b;
ll h[MAXN],mp[MAXN],p[MAXN];
void work(){
	if(a>b)swap(a,b);
	p[1]=a,p[n]=b;
	ll l=1,r=n;
	for(int i=1;i<n-1;i++){
		if(p[l]>p[r])p[++l]=h[i];
		else p[--r]=h[i];
	}
}
int main(){
	freopen("permutation.in","r",stdin);
	freopen("permutation.out","w",stdout);
	T=read();
	while(T--){
		n=read();
		pd=0;
		a=0,b=0;
		for(int i=1;i<=n;i++)mp[i]=0;
		for(int i=1;i<=n;i++)p[i]=0;
		for(int i=1;i<n;i++){
			h[i]=read();
			mp[h[i]]++;
			if(mp[h[i]]>1&&h[i]!=1)pd=1;
		}
//		ll a,b;
		for(int i=1;i<=n;i++){
			if(!mp[i]){
				if(!a)a=i;
				else if(!b)b=i;
				else pd=1;
			}
		}
		if(pd){
			cout<<"-1\n";
			continue;
		}
		if(b){
			if(h[n-1]!=1){
				cout<<"-1\n";
				continue;
			}else work();
//			cout<<"fuck1\n";
//			work();
		}else{
//			if(a==1)cout<<"-1\n";
			if(a>1&&h[n-1]==1){
				p[n]=a;
				for(int i=n-1;i;i--)p[i]=h[n-i];
			}else{
				cout<<"-1\n";
				continue;
			}
		}
		for(int i=1;i<=n;i++)cout<<p[i]<<" ";
		cout<<endl;
	}
	return 0;
}