#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
ll T,n,k; 
int main(){
	cin>>T;
	ll a[14]={-1,1,7,4,2,6,8,10,18,22,20,28,68,88};
	while(T--){
		cin>>n;
		if(n<=14){
			cout<<a[n-1]<<endl;
			continue;
		}
		k=n/7-1;
		cout<<a[n-k*7-1];
		for(int i=0;i<k;i++)cout<<"8";
		cout<<endl;
	}
}