C Programming pass values through functions [closed] - c

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I'm trying to get function2() to check the horizontal pairs and function3() to check the vertical pairs and pass both values back into main for function4() to use, I know not naming them properly is bad practice but bear with me...any help would be greatly appreciated...
My question is why I am getting the output of 0 for countX and countY and how to fix it..
#include<stdio.h>
#include<stdlib.h>
#include<time.h>
#define maxrow 20 //defines maxrow as a constant of 20
#define maxcol 30 //defines maxcol as a constant of 30
void function1(char array[][maxcol]);
int function2(char array[][maxcol]);
int function3(char array[][maxcol]);
void function4(int, int); //function to display the pairs count
int main( void )
{
int countX = 0;
int countY = 0;
srandom( (unsigned) time(NULL) );
char array[maxrow][maxcol];
function1(array);
function2(array);
function3(array);
function4 (countX, countY);
return ( 0 ) ;
}
void function1(char array[][maxcol])
{
int x = 0;
int y = 0;
for (x=0;x<maxrow;x++)
{
for (y=0;y<maxcol;y++)
{
array[x][y] = random() % 26 + 'A';
printf("%c ", array[x][y]);
}
printf("\n");
}
printf("\n");
}
int function2(char array[][maxcol])
{
int col = 0;
int row = 0;
int countX = 0;
for (row=0;row<maxrow-1;row++)
{
for (col=0;col<maxcol; col++)
{
if (array[row][col] == array[row+1][col])
{
countX++;
}
}
}
return(countX);
}
int function3(char array[][maxcol])
{
int col = 0;
int row = 0;
int countY = 0;
for(col=0;col<maxcol-1;col++)
{
for (row=0;row<maxrow;row++)
{
if (array[row][col] == array[row][col+1])
{
countY++;
}
}
}
return(countY);
}
void function4(int countX, int countY)
{
printf("\nNumber of horizontal pairs: %d\n", countX);
printf("\nNumber of vertical pairs: %d\n\n", countY);
}
output:
N E R J B Z Y R I T Y J P P B G K R A Z X O A Y V W S E V V
M L C F U D G S U O L U Z C M C K W T N V T B V T W U L B R
I N C K U Y N A R K Q E G Q J S U T P Q G M J I K E E G P H
X Z W C K Q A Z Q T L H Y S Z H K V A B L J O W R A A X G P
H F R D H B U K A M D O V D G W K S S N U D W K C P K C O Q
U V V L B F M X R O J U E F A K B K F V Z Z B V J D M V F D
L B A I M B N A Y E R K B V P B I S N N O N O R K Z U X U Z
C F D C N P G D S G J J Q K G H N Q C B F S O T J Y S D X M
E Z T H E J Z M M R U V C L I K U V B Y W I Q M C B L W E K
L L M E U Q P V E B O Y Z Q L J D G E G E D O X P S Y A P D
L A Q X G M P W I T Z W T A P F J S L O A R R O O G H N J W
S W Y K V E W K A E F C B Y C Q D M K Q C K I T A W B H L K
F D I F N D K M N M Q U Q T T T L Y F V P H H X C I V D R J
Q X O Y E E C Q Q R D G M V C H O N F V J U E Q T G A R M S
A E R O E V S I M I A R R O M T V D I C Y R X D K S J K J X
E L B V A I R U Q F F S Y Y G K T D N B G M V F R F Z C R J
A W W D R W L K T E P A W P Y D A R I P U O D P V U W V X O
G Z M C E F B S Q U W H U S X S X Z L G O F W U X S Q T P P
H V O V X V B Y N R U J A O D X I B Y V H P D D J A X Z T M
P D H F Y H A Z H N Q C Y T S C S B D R Y M G B R R B P Q V
Number of horizontal pairs: 0
Number of vertical pairs: 0

Answer 1

Here is why:
function2(array); // in main
function3(array); //in main
Both these functions return something but in main you just call them and don't collect the value returned .. Change above to this is main():
countX = function2(array); // this will put the value ( countX ) returned by this function in countX
countY = function3(array); // this will put the value ( countY ) returned by this function in countY

Answer 2

In the functions function2 and function3 the variables countX and countY (respectively) are local variables. Just like countX and countY in main are local inside main.
One way of solving your problem is to make the variables global, but I don't recommend that. Instead I recommend that you return the variables from the function, and assign to them in main.
So e.g. in function2:
int function2(...)
{
...
return countX;
}
And in main:
countX = function2(...);

Answer 3

Make countX and countY globals (and don't redeclare in the functions).
Or better yet - in main():
countX = function2(array);
countY = function3(array);
And a free tip: you don't need () on all the returns...