C++ Exercises: Sort an array of distinct elements according to absolute difference of array elements and with a given value

C++ Array: Exercise-17 with Solution

Write a C++ program to sort (in descending order) an array of distinct elements according to the absolute difference of array elements and with a given value.

Sample Solution:

C++ Code :

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

// Function to rearrange array elements based on their absolute difference from a given number 'x'
void rearrange_array_elements(int nums[], int n, int x)
{
    multimap<int, int> m; // Create a multimap to store absolute differences as keys and array elements as values

    // Insert elements into the multimap with their absolute differences from 'x' as keys
    for (int i = 0; i < n; i++)
        m.insert(make_pair(abs(x - nums[i]), nums[i])); // Use 'make_pair' to create a pair of (absolute difference, array element)

    int i = 0; // Initialize an index variable for accessing array elements after rearrangement
    // Traverse the multimap and rearrange the array based on sorted absolute differences
    for (auto t = m.begin(); t != m.end(); t++)
        nums[i++] = (*t).second; // Assign the elements sorted by absolute difference back to the original array
}

// Main function
int main()
{
    int nums[] = {0, 9, 7, 2, 12, 11, 20}; // 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: ";
    int x = 12; // Given number 'x'
    for (int i = 0; i < n; i++)
        cout << nums[i] << " "; // Output each element of the original array
    rearrange_array_elements(nums, n, x); // Rearrange the array elements based on their absolute differences from 'x'
    cout << "\nArray elements after rearrange: ";
    for (int i = 0; i < n; i++)
        cout << nums[i] << " "; // Output each element of the modified array after rearrangement
    return 0;
}

Sample Output:

Original array: 0 9 7 2 12 11 20 
Array elements after rearrange: 12 11 9 7 20 2 0     

Flowchart:

C++ Code Editor:

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