#include<iostream>
using namespace std;
int a[7]={88,16,24,22,20,28,68};
int b[8]={-1,-1,1,7,4,2,6,8}; 
int main(){
	int T;
	cin>>T;
	for(int t=0;t<T;t++){
		int n=0,cnt=0;
		cin>>n;
		if(n<=7){
			cout<<b[n]<<endl;
			continue;
		}
		while(n>=14){
			cnt++;
			n-=7;
		}
		cout<<a[n%7];
		for(int i=0;i<cnt;i++)cout<<8;
		cout<<endl;
	}
}