/**

题目：Trailing Zeroes (III)

链接：https://vjudge.net/contest/154246#problem/N

题意：假设n!后面有x个0.现在要求的是，给定x，要求最小的n；

思路：判断一个n!后面有多少个0，通过n/5+n/25+n/125+...

*/

#include<iostream>

#include<cstring>

#include<cstdio>

#include<algorithm>

#include<cmath>

using namespace std;

typedef long long ll;

const int maxn = *1e8+;

int num(int m)

{

    int cnt = ;

    while(m>){

        cnt += m/;

        m /= ;

    }

    return cnt;

}

int main()

{

    int T, cas=, q;

    cin>>T;

    while(T--)

    {

        scanf("%d",&q);

        int lo = , hi = maxn;

        int m;

        int mis = maxn;

        while(lo<=hi){

            m = (lo+hi)/;

            int t = num(m);

            if(t>=q){

                if(t==q) mis = min(mis,m);

                hi = m-;

            }else

            {

                lo = m+;

            }

        }

        if(mis==maxn)

            printf("Case %d: impossible\n",cas++);

        else

            printf("Case %d: %d\n",cas++,mis);

    }

    return ;

}