#include <stdio.h>
#include <stdlib.h>

#define TEST 5

int main(void){
    int *foo = (int*)malloc(sizeof(int) * TEST);
    for(int i = 0; i < TEST; i++)
        foo[i] = i;

    for(int i = 0; i < TEST; i++)
        printf("%d\n", foo[i]);
    printf("\n");

    foo = (int *)realloc(foo, sizeof(int) * (TEST + TEST));
    for(int i = TEST; i < TEST + TEST; i++)
        foo[i] = i + 10;

    for(int i = 0; i < TEST + TEST; i++)
        printf("%d\n", foo[i]);
    return 0;
}