#include <stdio.h>
#include <stdlib.h>
 
int main() {
    int *arr;
    int n, i;
 
    // Input array size
    printf("Enter number of elements: ");
    scanf("%d", &n);
 
    // Dynamically allocate memory for n integers
    arr = (int *)malloc(n * sizeof(int));
 
    // Check if memory allocation was successful
    if (arr == NULL) {
        printf("Memory allocation failed!\n");
        return 1;
    }
 
    // Input elements
    printf("Enter %d elements:\n", n);
    for (i = 0; i < n; i++) {
        scanf("%d", arr + i);
    }
 
    // Display elements
    printf("\nArray elements are:\n");
    for (i = 0; i < n; i++) {
        printf("%d ", *(arr + i));
    }
 
    // Free allocated memory
    free(arr);
 
    return 0;
}

#include <stdio.h>
#include <stdlib.h>
 
int main() {
    int *arr;          // pointer to hold base address of the array
    int n, i;
 
    printf("Enter number of elements: ");
    scanf("%d", &n);
 
    // allocate memory using calloc()
    arr = (int *)calloc(n, sizeof(int));
 
    // check if memory allocation is successful
    if (arr == NULL) {
        printf("Memory not allocated.\n");
        return 1;
    }
 
    // input elements
    printf("Enter %d elements:\n", n);
    for (i = 0; i < n; i++) {
        scanf("%d", &arr[i]);
    }
 
    // display elements
    printf("Array elements are:\n");
    for (i = 0; i < n; i++) {
        printf("%d ", arr[i]);
    }
 
    // free allocated memory
    free(arr);
 
    return 0;
}

#include <stdio.h>
#include <stdlib.h>
 
int main() {
    int *arr;           // pointer for dynamic array
    int n, newSize, i;
 
    printf("Enter number of elements: ");
    scanf("%d", &n);
 
    // allocate memory using calloc()
    arr = (int *)calloc(n, sizeof(int));
 
    if (arr == NULL) {
        printf("Memory not allocated.\n");
        return 1;
    }
 
    printf("Enter %d elements:\n", n);
    for (i = 0; i < n; i++) {
        scanf("%d", &arr[i]);
    }
 
    printf("Array elements before resizing:\n");
    for (i = 0; i < n; i++) {
        printf("%d ", arr[i]);
    }
 
    // ask for new size
    printf("\n\nEnter new size of the array: ");
    scanf("%d", &newSize);
 
    // reallocate memory using realloc()
    arr = (int *)realloc(arr, newSize * sizeof(int));
 
    if (arr == NULL) {
        printf("Memory reallocation failed.\n");
        return 1;
    }
 
    // input new elements if size increased
    if (newSize > n) {
        printf("Enter %d new elements:\n", newSize - n);
        for (i = n; i < newSize; i++) {
            scanf("%d", &arr[i]);
        }
    }
 
    printf("Array elements after resizing:\n");
    for (i = 0; i < newSize; i++) {
        printf("%d ", arr[i]);
    }
 
    // free memory
    free(arr);
 
    return 0;
}