To perform insert operation in a sorted array - arrays

Question

What is wrong with this code and where is the problem?
I ran this code many times but it's showing that the code is running but I am not getting any output.
Can you tell me where is the mistake?
#include <stdio.h>
int print_arr(int *arr, int n)
{ for(int i=0; i<=n; i++)
{
printf("%d ",arr[i]);
}
return 0;
}
int insert_ele(int *arr_a, int *arr_b, int n, int Key)
{
int i,j;
for(i=0, j=0; i<n; i++, j++)
{
if(arr_a[i]>Key)
{
arr_b[j] = Key;
arr_b[j+1] = arr_a[i];
j++;
}
else
{
arr_b[j] = arr_a[i];
}
}
return 0;
}
int main()
{
//code
int arr_a[] = {12, 16, 20, 40, 50, 70};
int arr_b[10];
int Key = 26;
int n = sizeof(arr_a)/sizeof(arr_a[0]);
int indx = insert_ele(arr_a, arr_b, n, Key);
print_arr(arr, n);
return 0;
}

Answer 1

For starters there is a typo in this statement
print_arr(arr, n);
It seems you mean
print_arr( arr_b, n + 1 );
The return type int of the function print_arr does not make a sense and is useless.
The first parameter of the function should have the qualifier const because the passed array is not being changed within the function.
The second parameter should have the type size_t.
This for loop
for(int i=0; i<=n; i++)
can invoke undefined behavior if the user of the function will pass the number of elements in the array in the second parameter n because in this case there will be an attempt to access memory beyond the array.
Again the return type int of the function insert_ele does not make a sense and is useless.
The first parameter should have the qualifier const because the source array is not being changed within the function. The parameter n should have the type size_t.
The function has a logical error.
Let's assume that the value of the variable Key is less than values of all elements of the array arr_a.
In this case the index j will be incremented twice and as a result you will have
b[0] = Key; b[2] = Key; b[4] = Key; and so on.
The logic of the function will be much clear if to split the for loop in two for loops.
The program can look the following way.
#include <stdio.h>
size_t insert_ele( const int *a, size_t n, int *b, int key )
{
size_t i = 0;
for ( ; i < n && !( key < a[i] ); i++ )
{
b[i] = a[i];
}
b[i] = key;
for ( ; i < n; i++ )
{
b[i+1] = a[i];
}
return i;
}
FILE * print_arr( const int *a, size_t n, FILE *fp )
{
for ( size_t i = 0; i < n; i++)
{
fprintf( fp, "%d ", a[i] );
}
return fp;
}
int main(void)
{
int a[] = { 12, 16, 20, 40, 50, 70 };
const size_t N = sizeof( a ) / sizeof( *a );
int b[10];
int key = 26;
size_t m = insert_ele( a, N, b, key );
fputc( '\n', print_arr( b, m, stdout ) );
return 0;
}
The program output is
12 16 20 26 40 50