C++ Exercises: Rearrange a given sorted array of positive integers

C++ Array: Exercise-15 with Solution

Write a C++ program to rearrange a given sorted array of positive integers.
Note: In final array, first element should be maximum value, second minimum value, third second maximum value, fourth second minimum value, fifth third maximum and so on.

Sample Solution:

C++ Code :

#include <iostream> // Header file for input/output stream
using namespace std; // Using the standard namespace

// Function to rearrange elements such that first element is the maximum value, second is minimum value, third is second maximum, and so on.
void rearrange_max_min(int nums[], int n)
{
    int temp[n]; // Temporary array to store rearranged elements
    int small_num = 0, large_num = n - 1; // Initialize variables to track positions of smallest and largest elements
    int result = true; // Variable to decide whether to pick maximum or minimum element

    // Loop to rearrange elements in the temporary array
    for (int i = 0; i < n; i++)
    {
        if (result)
            temp[i] = nums[large_num--]; // Place the largest element at even index positions
        else
            temp[i] = nums[small_num++]; // Place the smallest element at odd index positions

        result = !result; // Flip the result to switch between maximum and minimum elements
    }

    // Copy rearranged elements back to the original array
    for (int i = 0; i < n; i++)
        nums[i] = temp[i];
}

// Main function
int main()
{
    int nums[] = {0, 1, 3, 4, 5, 6, 7, 8, 10}; // Declaration and initialization of an integer array
    int n = sizeof(nums) / sizeof(nums[0]); // Calculate the number of elements in the array
    cout << "Original array: ";
    for (int i = 0; i < n; i++)
        cout << nums[i] << " "; // Output each element of the original array
    rearrange_max_min(nums, n); // Rearrange the array as per the requirement
    cout << "\nArray elements after rearranging: ";
    for (int i = 0; i < n; i++)
        cout << nums[i] << " "; // Output each element of the modified array
    return 0;
}

Sample Output:

Original array: 0 1 3 4 5 6 7 8 10 
Array elements after rearranging: 10 0 8 1 7 3 6 4 5    

Flowchart:

C++ Code Editor:

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