LinuxQuestions.org - ascending order

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- - ascending order (https://www.linuxquestions.org/questions/programming-9/ascending-order-345807/)

how can i check if the array element in ascending order using recursive ?

Shall we just a pick a programming language at random and hope that's the one you're asking about?

Quote:

Shall we just a pick a programming language at random and hope that's the one you're asking about?

Why not? :p
Here's an implementation in C++.

Code:

#include <iostream>



using std::cout;

using std::endl;



bool isInAscendingOrder(const int*, const unsigned int);

static bool checkArray(const int*, const int*, const int* const);



int main()

{

    const unsigned int s = 10;

    int a[s] = { 0, 1, 2, 4, 3, 5, 6, 7, 8, 9 };



    if (isInAscendingOrder(a, s))

        cout << "Array \"a\" is in ascending order." << endl;

    else

        cout << "Array \"a\" is not in ascending order." << endl;



    return 0;

}



bool isInAscendingOrder(const int* arr, const unsigned int size)

{

    if (size == 0)

        return false;



    const int* e1 = arr;

    const int* e2 = arr + 1;

    const int* end = arr + size;        // First address beyond the end of the array is always valid.



    return checkArray(e1, e2, end);

}



static bool checkArray(const int* a, const int* b, const int* const c)

{

    if (b == c)                        // We've checked every element of the array and it's in order.

        return true;

    else if (*b < *a)                  // We've found two elements that aren't in order.

        return false;



    return checkArray(++a, ++b, c);    // Check the next element.

}

And here's a C one that even tells you were the order breaks and uses one less function than that C++ version ;)

Code:

#include <stdio.h>



int chk_ascending(int *array, int index, int size)

{

  if(index >= size - 1)

    return 0;

  if(array[index] > array[index + 1])

    return index + 1;



  return chk_ascending(array, index + 1, size);

}



int main(void)

{

  int a[] = { 0, 1, 2, 4, 3, 5, 6, 7, 8, 9 };

  int num_a = 10;

  int rv;



  if(!(rv = chk_ascending(a, 0, num_a)))

    puts("Array \"a\" is in ascending order.");

  else

    printf("Array \"a\" breaks ascending order at index %d.\n", rv);



  return 0;

}

Well done, I like your version better.
My coding skills are a little rusty :D