#include<iostream>
#include<cstdio>
#include<cstring>

using namespace std;

char s[550][2200];
int Next[550][2200];

int Judge(int w, int o)
{
    int i = 0 , j = 0;
    int l1, l2;
    l1 = strlen(s[w]);
    l2 = strlen(s[o]);

    while(i < l1 && j < l2)
    {
        if(s[w][i] == s[o][j] || i == -1)
        {
            i++;
            j++;
        }
        else
            i = Next[w][i];

        if(i == l1)
        {
            return true;
        }
    }
    return false;
}

void getNext(int q)
{
    int j, k;
    int i = strlen(s[q]);
    j = 0;
    k = -1;
    Next[q][0] = -1;

    while(j < i)
    {
        if(k == -1 || s[q][j] == s[q][k])
        {
            j++;
            k++;
            Next[q][j] = k;
        }
        else
            k = Next[q][k];
    }
}

int main()
{
    int t, n, index, l = 1;
    scanf("%d", &t);

    while(t--)
    {
        scanf("%d", &n);
        for(int i = 0; i < n; i++)
        {
            scanf("%s", s[i]);
            getNext(i);
        }
        index = -1;
        int q;
        for(int i = n-2; i >= 0; i--)
        {
            if(!Judge(i, i+1))  找到一个字符串不满足前后是子串关系后，从后向前找最大的不满足子串的串
            {
                q = i;
                for(int j = n-1; j > q; j--)
                {
                    if(!Judge(q, j))
                        index = index > j ? index : j;
                 }
            }
        }
        if(index == -1)
            printf("Case #%d: %d\n", l++, index);
        else
            printf("Case #%d: %d\n", l++, index+1);
    }
    return 0;
}