prirityQueqe.c

#include <stdio.h>
int size = 0;
void swap(int *a, int *b)
{
    int temp = *b;
    *b = *a;
    *a = temp;
}

// Function to heapify the tree
void heapify(int array[], int size, int i)
{
    if (size == 1)
    {
        printf("Single element in the heap");
    }
    else
    {
        // Find the largest among root, left child and right child
        int largest = i;
        int l = 2 * i + 1;
        int r = 2 * i + 2;
        if (l < size && array[l] > array[largest])
            largest = l;
        if (r < size && array[r] > array[largest])
            largest = r;

        // Swap and continue heapifying if root is not largest
        if (largest != i)
        {
            swap(&array[i], &array[largest]);
            heapify(array, size, largest);
        }
    }
}

// Function to insert an element into the tree
void insert(int array[], int newNum)
{
    int i;
    if (size == 0)
    {
        array[0] = newNum;
        size += 1;
    }
    else
    {
        array[size] = newNum;
        size += 1;
        for (i = size / 2 - 1; i >= 0; i--)
        {
            heapify(array, size, i);
        }
    }
}

// Function to delete an element from the tree
void deleteRoot(int array[], int num)
{
    int i;
    for (i = 0; i < size; i++)
    {
        if (num == array[i])
            break;
    }

    swap(&array[i], &array[size - 1]);
    size -= 1;
    for (i = size / 2 - 1; i >= 0; i--)
    {
        heapify(array, size, i);
    }
}

// Print the array
void printArray(int array[], int size)
{
    int i;
    for (i = 0; i < size; ++i)
        printf("%d ", array[i]);
    printf("\n");
}

// Driver code
int main()
{
    int array[10];

    int n, i, ele;
    printf("Enter the size of array: ");
    scanf("%d", &n);
    printf("Enter the elements:\n");
    for (i = 0; i < n; i++)
    {
        printf("A[%d]: ", i);
        scanf("%d", &ele);
        insert(array, ele);
    }

    printf("Max-Heap array: ");
    printArray(array, size);

    deleteRoot(array, array[size]);

    printf("After deleting an element: ");

    printArray(array, size);
}