2025-12-15 23:48:33 +01:00

113 lines
2.6 KiB
C

#include <stdlib.h>
#include <stdio.h>
#include <time.h>
#include <string.h>
#include "numbers.h"
#include "bintree.h"
// TODO: getDuplicate und createNumbers implementieren
/* * * Erzeugen eines Arrays mit der vom Nutzer eingegebenen Anzahl an Zufallszahlen.
* Sicherstellen, dass beim Befüllen keine Duplikate entstehen.
* Duplizieren eines zufälligen Eintrags im Array.
* in `getDuplicate()`: Sortieren des Arrays und Erkennen der doppelten Zahl durch Vergleich benachbarter Elemente. */
// Returns len random numbers between 1 and 2x len in random order which are all different, except for two entries.
// Returns NULL on errors. Use your implementation of the binary search tree to check for possible duplicates while
// creating random numbers.
static void duplicateRandomEntry(unsigned int *numbers, unsigned int len)
{
if (!numbers || len < 2)
return;
unsigned int src = rand() % len;
unsigned int dst = rand() % len;
while (dst == src)
dst = rand() % len;
numbers[dst] = numbers[src];
}
static int compare(const void *a, const void *b)
{
unsigned int x = *(const unsigned int *)a;
unsigned int y = *(const unsigned int *)b;
return (x > y) - (x < y);
}
unsigned int *createNumbers(unsigned int len)
{
if (len < 2)
return NULL;
unsigned int *numbers = malloc(sizeof(unsigned int) * len);
if (!numbers)
return NULL;
static int seeded = 0;
if (!seeded) {
srand((unsigned)time(NULL));
seeded = 1;
}
TreeNode *root = NULL;
unsigned int i = 0;
while (i < len)
{
unsigned int val = (rand() % (2 * len)) + 1;
int isDup = 0;
root = addToTree(root, &val, sizeof(unsigned int), compare, &isDup);
if (!root)
{
free(numbers); // malloc-Fehler
return NULL;
}
if (!isDup)
numbers[i++] = val;
}
duplicateRandomEntry(numbers, len);
clearTree(root);
return numbers;
}
// Returns only the only number in numbers which is present twice. Returns zero on errors.
unsigned int getDuplicate(const unsigned int numbers[], unsigned int len)
{
if (!numbers || len < 2)
{
return 0;
}
unsigned int *copy = (unsigned int *)malloc(len * sizeof(unsigned int));
if (!copy)
{
return 0;
}
memcpy(copy, numbers, len * sizeof(unsigned int));
qsort(copy, len, sizeof(unsigned int), compare);
unsigned int dup = 0;
for (unsigned int i = 1; i < len; i++)
{
if (copy[i] == copy[i - 1])
{
dup = copy[i];
break;
}
}
free(copy);
return dup;
}