Using Functions to Pass an Array - c

Question

Hi, i am using a Function for the first time for my 2-D Array and so far i have been told it is right but i am having a problem with the 'For Loop'.
Specifically repeating the printed statement and numbers until the array is full, and also shows the specific array you are filling. (As the image shows).
This only prints 1 statement with 1 Array, whilst 4 numbers afterwards.. How could i get each number printed after each statement? I have tried the only way i know which made it worse.
Incorrectly Looped printed statement
Code below:
void DisplayArray(int a[2][2]);
int main()
{
int a[2][2], i, j, k;
/*Counter variables for the loop*/
printf ("***** Functions ***** \n");
for (i=0; i<2; i++)
for(j=0; j<2; j++)
printf("\n Enter numeric values for each Array [%d] [%d]: \n", i, j);
scanf("%d", &a[i][j]);
DisplayArray(a);
return 0;
}
void DisplayArray(int a[2][2])
{
int i, j;
/*Displaying Array elements*/
printf("\n The 2-D Array contains : \n");
for(i=0; i<2; i++)
for(j=0; j<2; j++)
printf("%d \n" , a[i][j]);/*[i] name of 1 Array - [j] name of 2 Array*/
if(j==2)
printf("\n");
}

Answer 1

You forgot to properly define the scope of the inner for loops.
The lines
for (i=0; i<2; i++)
for(j=0; j<2; j++)
printf("\n Enter numeric values for each Array [%d] [%d]: \n", i, j);
scanf("%d", &a[i][j]);
are equivalent to:
for (i=0; i<2; i++)
for(j=0; j<2; j++)
printf("\n Enter numeric values for each Array [%d] [%d]: \n", i, j);
// Outside of both the for loops.
scanf("%d", &a[i][j]);
The indent expresses the intent to a human reader but not to the computer.
You need to use:
for (i=0; i<2; i++)
for(j=0; j<2; j++)
{ // Add
printf("\n Enter numeric values for each Array [%d] [%d]: \n", i, j);
scanf("%d", &a[i][j]);
} // Add
To make the code more readable add an explicit scope for the outer for loops too.
for (i=0; i<2; i++)
{ // Add
for(j=0; j<2; j++)
{ // Add
printf("\n Enter numeric values for each Array [%d] [%d]: \n", i, j);
scanf("%d", &a[i][j]);
} // Add
} // Add
Make similar changes to the other loops.

Answer 2

Your for loops are probably not acting as you intended, because without the curly braces, they will only act on the first statement.
void DisplayArray(int a[2][2]);
int main()
{
int a[2][2], i, j, k;
/*Counter variables for the loop*/
printf ("***** Functions ***** \n");
for (i=0; i<2; i++)
{
for(j=0; j<2; j++)
{
printf("\n Enter numeric values for each Array [%d] [%d]: \n", i, j);
scanf("%d", &a[i][j]);
}
}
DisplayArray(a);
return 0;
}
void DisplayArray(int a[2][2])
{
int i, j;
/*Displaying Array elements*/
printf("\n The 2-D Array contains : \n");
for(i=0; i<2; i++)
{
for(j=0; j<2; j++)
{
printf("%d \n" , a[i][j]);/*[i] name of 1 Array - [j] name of 2 Array*/
if(j==2)
printf("\n");
}
}
}

Answer 3

You're missing some curly braces. Change to this:
for (i=0; i<2; i++)
for(j=0; j<2; j++) {
printf("\n Enter numeric values for each Array [%d] [%d]: \n", i, j);
scanf(" %d", &a[i][j]);
DisplayArray(a);
}
and
for(i=0; i<2; i++)
for(j=0; j<2; j++) {
printf("%d \n" , a[i][j]);
if(j==2)
printf("\n");
}
Also, note that if(j==2) will never evaluate to true. When j is equal to 2, the loop is over. You should change this to 1. I would also suggest to remove \n in the innermost printf statement.
Complete code:
#include <stdio.h>
void DisplayArray(int a[2][2]);
int main()
{
int a[2][2], i, j, k;
/*Counter variables for the loop*/
printf ("***** Functions ***** \n");
for (i=0; i<2; i++)
for(j=0; j<2; j++) {
printf("\n Enter numeric values for each Array [%d] [%d]: \n", i, j);
scanf(" %d", &a[i][j]);
DisplayArray(a);
}
return 0;
}
void DisplayArray(int a[2][2])
{
int i, j;
/*Displaying Array elements*/
printf("\n The 2-D Array contains : \n");
for(i=0; i<2; i++)
for(j=0; j<2; j++) {
printf("%d " , a[i][j]);/*[i] name of 1 Array - [j] name of 2 Array*/
if(j==1)
printf("\n");
}
}