thebbqcode

/* 
   This little snippet is a method of iterating
   an array without using loops of any kind, rather
   we can use recusion to do all our work
*/
 
#include <stdio.h>
 
int p[] = { 20, 30, 1, 2, 5, 3 };           // our test array
int size_ = sizeof( p ) / sizeof ( int );   // determins the array size using
                                            // simple maths sizeof the array, divided
                                            // by the size of its parts.
 
 
/*
    initially pass size_ - 1 to the function
    ass this is the last element of the array
    and we wish to move in reverse order towards 0
    the first element in the array
*/
void printArrayReverse( int index )
{
    if ( index < 0 )    // if we have passed beginning of array
        return;         // must return to terminate the recusion of void func
 
    printf( "%i\n", p[index] );
 
    // use recursion to get the previous element
    // in the array ( current pos - 1 )
    printArrayReverse( index - 1 );
}
/*
   initially pass zero to the function call as
   we wish to begin from zero moving forward
   through the elements of the array
*/
void printArray( int index )
{
    if ( index >= size_ )   // reached end of array
        return;
    printf( "%i\n", p[index] );
    printArray( index + 1 );    // user recursion to get and print
                                // next element ( current pos + 1 )
}
 
int main()
{
    printArrayReverse( size_ - 1 );
    printArray( 0 );
    return 0;
}