C language An array of 3 rows and 4 columns is entered. 1 2 1 1

C language
An array of 3 rows and 4 columns is entered.
1 2 1 1
4 3 6 8
5 8 4 7
There are 4 duplicate items to be removed (1 1 8 4). 8 items remain. You can make a 3-by-3 square array and pad it with one element equal to 0. Result.
1 2 4
3 6 8
5 7 0
Example of the second.
An array of one line and 8 elements per line. 1 1 1 2 3 3 3 3.
There are 5 items to be removed (1 1 3 3 3 3).
3 elements remain. (1 2 3). Of these, a 2 by 2 square array. Result.
1 2
3 0