Problem Statement:
Ethan wants to draw a painting on an m×n board. He can draw some strips on the board using a paintbrush of width one. In each step, he must choose a new color and paint a full column or a full row.
He has a great image to be drawn on the board, but he doesn?t know which color to use first. You must help him in finding out the order of colors.

Input Format:
There are multiple test cases in the input. The first line of each test case contains two integers m and n, the size of the board (0< m, n <100). Following the first line, there are m lines with n integers denoting the color in each cell. All the colors are positive integer numbers less than 10000. The input is terminated with
a single line containing two consecutive zeros.

Output Format:
For each test case, write a single line containing the order of colors used to paint the board. If there are several answers, output the one which is lexicographically smallest (considering each number as a symbol).

Sample Input:
4 4 1 5 4 3 6 5 6 6 2 2 2 2 1 5 4 3 3 2 1 1 2 3 2 3 0 0

Sample Output:
1 3 4 6 5 2 2 3 1

Added by: alaa.jrad
Added at: 2014-09-14 07:00:00 UTC
Time Limit: 3 seconds
Partial score: No