Puzzle DD38

Shift array elements N positions left; the high N elements get 0

[M-10] Write a function that moves array elements N positions left. The first N entries are discarded, and the last N elements are set to zero.

   0    1    2    3    4    5    6    7    8    9
  10   11   12   13   14   15   16   17   18   19

Shift Left 7 Positions:
   7    8    9   10   11   12   13   14   15   16
  17   18   19    0    0    0    0    0    0    0

Here is a testing framework:

#include <stdio.h>
#include <stdlib.h>

/* Puzzle D38 -- shift array elements N positions left; */
/*               the last N elements get 0;         */
/*               the first N elements are discarded */

void shiftLeftNArray( int size, int arr[], int shift )
{

}

void fillArrayInOrder( int size, int arr[] )
{
  int j;
  
  for ( j=0; j<size; j++ )
  {
    arr[j] = j;
  }
}

void printArray( int size, int arr[] )
{
  const int N = 10;
  int j;
  
  for ( j=0; j<size; j++ )
  {
    if ( j%N == N-1 )
      printf("%4d\n", arr[j] );
    else
      printf("%4d ", arr[j] );    
  }
}

int main()
{
  const int SIZE = 20;
  int x[ SIZE ];
  int shift = 7;
  
  fillArrayInOrder( SIZE, x );
  printArray( SIZE, x );
  printf("\nShift Left %d Positions:\n", shift);
  shiftLeftNArray( SIZE, x, shift );
  printArray( SIZE, x );
    
  printf("\n\n");
  return 0;
}