以下是~~c++~~代码

#include<bits/stdc++.h>  
using namespace std;

int main()
{  
    int t;
    cin >> t;
    while(t--)
    {
        int n;
        cin >> n;
        if(n == 1)
        {
            cout << -1 << endl;
            continue;
        }
        if(n == 3)
        {
            cout << 7 << endl;
            continue;
        }
        if(n == 4)
        {
            cout << 4 << endl;
            continue;
        }
        if(n == 10)
        {
            cout << 22 << endl;
            continue;
        }
        int r = n % 7;
        if(!r)
        {
            for(int i = 1;i <= n / 7;i++)
            {
                cout << 8;
            }
        }
        if(r == 1)
        {
            cout << 10;
            for(int i = 1;i <= n / 7 - 1;i++)
            {
                cout << 8;
            }
        }
        if(r == 2)
        {
            cout << 1;
            for(int i = 1;i <= n / 7;i++)
            {
                cout << 8;
            }
        }
        if(r == 3)
        {
            cout << 200;
            for(int i = 1;i <= n / 7 - 2;i++)
            {
                cout << 8;
            }
        }
        if(r == 4)
        {
            cout << 20;
            for(int i = 1;i <= n / 7 - 1;i++)
            {
                cout << 8;
            }
        }
        if(r == 5)
        {
            cout << 2;
            for(int i = 1;i <= n / 7;i++)
            {
                cout << 8;
            }
        }
        if(r == 6)
        {
            cout << 6;
            for(int i = 1;i <= n / 7 - 1;i++)
            {
                cout << 8;
            }
        }
        cout << endl;
    }
}