#include <stdlib.h>
#include <stdio.h>
void print_mas(int * ptr, int N)
{
    for(int i = 0; i < N; i++)
        printf("%d   ",ptr[i]);
    printf("\n");
}
int main(int argc, char const *argv[])
{
    int* arr;   //
    int N;      // int arr[N];
    scanf("%d", &N);

    arr = (int*)calloc(N, sizeof(int));
    for(int i = 0; i < N; i++)
        arr[i] = i*2;
    print_mas(arr, N);
    N++;
    arr = (int*)realloc(arr,N * sizeof(int));
    arr[N-1] = 10;
    print_mas(arr, N);

    N = 1;
    arr = (int*)realloc(arr, N * sizeof(int));
    print_mas(arr, N);
    free(arr);
    return 0;
}