same_value_as_index_v1.c

/*

    same_value_as_index_v1.c

    Suppose you are given a sorted array, such as A = {-5, -1, 2, 4, 6}.
    Write an algorithm which takes this sorted array as input and
    returns as output an ‘index’,
    if the value stored at A[index] is same as ‘index’,
    else return -1.

    Example, for array A, the value returned is 2, as A[2] == 2.


    You can find all my C programs at Dragan Milicev's pastebin:

    https://pastebin.com/u/dmilicev

*/

#include <stdio.h>


// Returns index if A[i] = i, otherwise returns -1.
int same_value_as_index( int A[], int n, int i)
{
    if( A[i] == i )
        return i;
    else
        return -1;
}


int main(void)
{
    int A[] = {-5, -1, 2, 4, 6};
    int i, n;

    n = sizeof(A) / sizeof(A[0]);   // or
    //n = sizeof(A) / sizeof(int);

    for( i=0; i<n; i++)
    {
        printf("\n i = %d \t A[%d] = %d \t same_value_as_index(A,n,i) = %d \n",
                i, i, A[i], same_value_as_index(A,n,i) );
    }

    return 0;

} // main()