Example: Array Deletion in C in C

// Array Deletion in C
#include <stdio.h>

#define MAX_SIZE 10 // Define a maximum physical size for the array

// Function to print the array (repeated for clarity, but ideally in a common utility)
void printArray(int arr[], int size) {
    int i;
    for (i = 0; i < size; i++) {
        printf("%d ", arr[i]);
    }
    printf("\n");
}

// Function to delete an element from a specific position
// Returns 1 on success, 0 on failure (e.g., array empty or invalid position)
int deleteElement(int arr[], int *currentSize, int position) {
    // Step 1: Check if the array is empty
    if (*currentSize <= 0) {
        printf("Error: Array is empty. Cannot delete.\n");
        return 0;
    }

    // Step 2: Check for valid deletion position
    // Position must be between 0 and currentSize - 1 (inclusive)
    if (position < 0 || position >= *currentSize) {
        printf("Error: Invalid position for deletion.\n");
        return 0;
    }

    // Step 3: Shift elements to the left to overwrite the element at 'position'
    // Start from the element *after* the deletion point
    for (int i = position; i < *currentSize - 1; i++) {
        arr[i] = arr[i + 1];
    }

    // Step 4: Decrement the current size of the array
    (*currentSize)--;

    return 1; // Success
}

int main() {
    int arr[MAX_SIZE] = {5, 10, 20, 25, 30, 40, 50, 60}; // Array after previous insertions
    int currentSize = 8;

    printf("Original array for deletion: ");
    printArray(arr, currentSize);

    // Delete element at position 2 (which is 20)
    printf("Attempting to delete element at position 2...\n");
    if (deleteElement(arr, &currentSize, 2)) {
        printf("Array after deletion: ");
        printArray(arr, currentSize);
    }

    // Delete element at position 0 (which is 5)
    printf("Attempting to delete element at position 0...\n");
    if (deleteElement(arr, &currentSize, 0)) {
        printf("Array after deletion: ");
        printArray(arr, currentSize);
    }

    // Delete element at the new last position (which is 60)
    printf("Attempting to delete element at last position (currentSize - 1)...\n");
    if (deleteElement(arr, &currentSize, currentSize - 1)) {
        printf("Array after deletion: ");
        printArray(arr, currentSize);
    }

    // Try to delete from an invalid position
    printf("Attempting to delete from an invalid position (large index)...\n");
    deleteElement(arr, &currentSize, currentSize); // currentSize is an invalid index

    printf("Current size after multiple deletions: %d\n", currentSize);

    return 0;
}