#include<iostream>
#include<cstdio>
#include<cstring>
#include<cmath>
#include<algorithm>
#include<string>
#include<map>
#include<set>
#include<vector>
#include<cassert>
#define LL long long
#define LD double
using namespace std;
set<long long>mp;
int mi[30];
bool getwei(int s,int w){return (s&mi[w])>0;}
int bitcount(int x)
{
    int ans=0;
    for (int i=0;i<=20;i++) if (getwei(x,i)) ans++;
    return ans;
}
void init()
{
    mi[0]=1;for (int i=1;i<=22;i++) mi[i]=mi[i-1]*2;
    for (int i=2;i<=18;i+=2)
    for (int j=0;j<mi[i];j++)
    {
        if (bitcount(j)!=i/2) continue;
        long long p=0;
        for (int k=0;k<i;k++)
        {
            if (getwei(j,k)) p=p*10+4;else p=p*10+7;
        }
        mp.insert(p);
    }
}
long long work(long long x)
{
    if (mp.lower_bound(x)!=mp.end()) return *mp.lower_bound(x);else return -1;
}
int main()
{
    init();
    int t;scanf("%d",&t);
    while (t--)
    {
        long long n;scanf("%I64d",&n);
        long long ans=work(n);
        if (ans!=-1) printf("%I64d\n",ans);else printf("44444444447777777777\n");
    }
}