Merge pull request kelvins#248 from andersonhsporto/radix-sort

Add: radix sort in ANSI C

Author: kelvins

README.md

@@ -3087,8 +3087,8 @@ In order to achieve greater coverage and encourage more people to contribute to
         <tr>
             <td><a href="https://en.wikipedia.org/wiki/Radix_sort">Radix Sort</a></td>
             <td> <!-- C -->
-                <a href="./CONTRIBUTING.md">
-                    <img align="center" height="25" src="./logos/github.svg" />
+                <a href="./src/c/RadixSort.c">
+                    <img align="center" height="25" src="./logos/c.svg" />
                 </a>
             </td>
             <td> <!-- C++ -->

src/c/RadixSort.c

@@ -0,0 +1,65 @@
+#include <stdio.h>
+
+void print_array(int array[], int size)
+{
+	printf("[ ");
+	for (int i = 0; i < size; i++)
+	{
+		printf("%d ", array[i]);
+	}
+	printf("]\n");
+}
+
+int get_max(int array[], int size)
+{
+	int max = array[0];
+	for (int i = 1; i < size; i++)
+	{
+		if (array[i] > max)
+			max = array[i];
+	}
+	return max;
+}
+
+void radix_sort(int array[], int size)
+{
+	int i;
+	int semi_sorted[size];
+	int significant_digit = 1;
+	int largest_number = get_max(array, size);
+
+	while (largest_number / significant_digit > 0)
+	{
+		int bucket[10] = {0};
+		for (i = 0; i < size; i++)
+		{
+			bucket[(array[i] / significant_digit) % 10]++;
+		}
+		for (i = 1; i < 10; i++)
+		{
+			bucket[i] += bucket[i - 1];
+		}
+		for (i = size - 1; i >= 0; i--)
+		{
+			semi_sorted[--bucket[(array[i] / significant_digit) % 10]] = array[i];
+		}
+		for (i = 0; i < size; i++)
+		{
+			array[i] = semi_sorted[i];
+		}
+		significant_digit *= 10;
+	}
+}
+
+int main()
+{
+	int array[10] = {45, 75, 89, 12, 34, 9, 67, 23, 90, 11};
+	printf("Unsorted Array\n");
+	print_array(array, 10);
+
+	radix_sort(array, 10);
+
+	printf("Sorted Array\n");
+	print_array(array, 10);
+	return 0;
+}