#include<bits/stdc++.h>
using namespace std;
int f[22]={0,-1,1,7,4,2,6,8,10,18,22,20,28,68,88,108,188,200,208,288,688,888};
int main()
{
	int a;
	cin>>a;
	while(a--)
	{
		int n,minn=2e9;
		cin>>n;
		if(n<=14)
		{
			cout<<f[n];
		}
		else
		{
			cout<<f[n%7+14];
			for(int i=1;i<=n/7-2;i++)
			{
				cout<<8;
			}
		}
		cout<<endl;
	}
	return 0;
}

先用爆搜找规律然后得出代码