Create generateUniqueRandIntegers.c

Author: prathwik0

Diff for: helperCode/generateUniqueRandIntegers.c

@@ -0,0 +1,80 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+
+int *generateUniqueRandIntegers(int min, int max, int count)
+{
+    if (count > (max - min + 1))
+    {
+        printf("Error: Cannot generate more unique random numbers than the range allows.\n");
+        return NULL;
+    }
+
+    if (min > max)
+    {
+        printf("Error: Invalid range.\n");
+        return NULL;
+    }
+
+    int rangeSize = max - min + 1;
+    int *numbers = malloc(rangeSize * sizeof(int));
+    if (numbers == NULL)
+    {
+        printf("Error: Memory allocation failed.\n");
+        return NULL;
+    }
+
+    // Initialize the array
+    for (int i = 0; i < rangeSize; i++)
+    {
+        numbers[i] = min + i;
+    }
+
+    // Shuffle the array using Fisher-Yates algorithm
+    srand(time(NULL));
+    for (int i = rangeSize - 1; i > 0; i--)
+    {
+        int j = rand() % (i + 1);
+        int temp = numbers[i];
+        numbers[i] = numbers[j];
+        numbers[j] = temp;
+    }
+
+    // Create a new array to store the selected unique random numbers
+    int *selectedNumbers = malloc(count * sizeof(int));
+    if (selectedNumbers == NULL)
+    {
+        printf("Error: Memory allocation failed.\n");
+        free(numbers);
+        return NULL;
+    }
+
+    // Copy the first 'count' elements from the shuffled array to the selectedNumbers array
+    for (int i = 0; i < count; i++)
+    {
+        selectedNumbers[i] = numbers[i];
+    }
+
+    free(numbers);
+    return selectedNumbers;
+}
+
+int main()
+{
+    int min = 1;       // Minimum value
+    int max = 1000000; // Maximum value
+    int count = 50000; // Number of unique random numbers to generate
+
+    int *randomArray = generateUniqueRandIntegers(min, max, count);
+    if (randomArray != NULL)
+    {
+        printf("Generated unique random numbers:\n");
+        for (int i = 0; i < count; i++)
+        {
+            printf("%d\n", randomArray[i]);
+        }
+        free(randomArray);
+    }
+
+    return 0;
+}