Memory Management: malloc, calloc, realloc, and free in C

 Memory Management: malloc, calloc, realloc, and free in C

C provides functions for dynamic memory allocation and deallocation. malloc is used to allocate a block of memory, calloc initializes the allocated memory to zero, realloc changes the size of an allocated block, and free deallocates the memory.

#include <stdio.h>

#include <stdlib.h>

int main() {

    int* nums = (int*)malloc(5 * sizeof(int));

    if (nums == NULL) {

        printf("Memory allocation failed.\n");

        return 1;

    }

    for (int i = 0; i < 5; i++) {

        nums[i] = i + 1;

    }

    for (int i = 0; i < 5; i++) {

        printf("%d ", nums[i]);

    }

    printf("\n");

    // Resizing the allocated memory

    int* resizedNums = (int*)realloc(nums, 10 * sizeof(int));

    if (resizedNums == NULL) {

        printf("Memory reallocation failed.\n");

        free(nums); // Free original memory if reallocation fails

        return 1;

    }

    for (int i = 5; i < 10; i++) {

        resizedNums[i] = i + 1;

    }

    for (int i = 0; i < 10; i++) {

        printf("%d ", resizedNums[i]);

    }

    printf("\n");

    free(resizedNums); // Deallocate the memory

    return 0;

}

This example demonstrates allocating memory for an array of integers, resizing the memory, and freeing the allocated memory.