How to Find Median of Numbers in an Array in C?

#include <stdio.h>
#include <stdlib.h>

void swap(int* a, int* b) {
    int temp = *a;
    *a = *b;
    *b = temp;
}

// Function to partition array around pivot element
int partition(int arr[], int l, int r) {
    int pivot = arr[r];
    int i = l;

    for (int j = l; j < r; j++) {
        if (arr[j] < pivot) {
            swap(&arr[i], &arr[j]);
            i++;
        }
    }
    swap(&arr[i], &arr[r]);
    return i;
}

void medianHelper(int arr[], int l, int r, int k, int* a, int* b) {
    if (l <= r) {
        int pi = partition(arr, l, r);

        // If partition index matches k, we found one of the medians
        if (pi == k) {
            *b = arr[pi];
            if (*a != -1)
                return;
        }
        // If partition index matches k - 1, we found the other median
        else if (pi == k - 1) {
            *a = arr[pi];
            if (*b != -1)
                return;
        }

        // If partition index is greater than or equal to k, recurse on the left
        if (pi >= k)
            medianHelper(arr, l, pi - 1, k, a, b);
        else
            // Recurse on the right
            medianHelper(arr, pi + 1, r, k, a, b);
    }
}

// Function to find the median of the array
int findMedian(int arr[], int n) {
    int a = -1, b = -1, m;

    // If n is odd
    if (n % 2 == 1) {
        medianHelper(arr, 0, n - 1, n / 2, &a, &b);
        m = b;
    } else {
        // If n is even
        medianHelper(arr, 0, n - 1, n / 2, &a, &b);
        m = (a + b) / 2;
    }

    return m;
}

int main() {
    int arr[] = {1, 3, 5, 2, 4};
    int n = sizeof(arr) / sizeof(arr[0]);

    printf("%d", findMedian(arr, n));
    return 0;
}