#include <stdlib.h>
#include <stdio.h>
 
void retorna_algo(int size, int* destino){
  if (size == 1){
    *destino = 1;
  } else if (size == 3) {
    memcpy(destino, (int[]){1, 2, 3}, 3*sizeof(int));
  }
}
 
int main(void) {
  int *ponteiro;
 
  ponteiro = malloc(sizeof(int));
  retorna_algo(1, ponteiro);
  printf("%d\n", *ponteiro); // Escreve "1" - como esperado
 
  ponteiro = realloc(ponteiro, sizeof(int)*3);
  retorna_algo(3, ponteiro);
 
  printf("%d | %d | %d\n", ponteiro[0], ponteiro[1], ponteiro[2]);
  // Escreve "1 | 0 | 0", basicamente mantendo o valor zerado do malloc e realloc
 
  return 0;
}

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