C :: How To Compare 2D Array Rows Separately

I am trying to write a program that prints a 2d array to the screen and then compares each row and column to see if there is any pairs of letters. basically something that looks like this:

---------------------------
V T A Y U C B
D F W Q Q C R
D A L Y M F G
O A S S D T I

Number of horizontal pairs: 2
Number of vertical pairs: 3
---------------------------

so far this is my code below, but i dont know how to approach the comparisons

Code:

#include<stdio.h>
#include<stdlib.h>
#include<time.h>
int main( void )

[code]....