Super Number

Don’t you think 162456723 very special? Look at the picture below if you are unable to find its speciality. (a|b means ‘b is divisible by a’) Figure: Super Numbers Given n, m (0 < n < m < 30), you are to find a m-digit positive integer X such that for every i (n ≤ i ≤ m), the first i digits of X is a multiple of i. If more than one such X exists, you should output the lexicographically smallest one. Note that the first digit of X should not be 0. Input The first line of the input contains a single integer t (1 ≤ t ≤ 15), the number of test cases followed. For each case, two integers n and m are separated by a single space. Output For each test case, print the case number and X. If no such number, print ‘-1’. Sample Input 2 1 10 3 29 Sample Output Case 1: 1020005640 Case 2: -1