Merge pull request #205 from MJ-thunder/add-radix-sort-java

Added Radix Sort Algorithm in Java (Java/sorting/RadixSort.java)

Author: admirerr

Java/sorting/RadixSort.java

@@ -0,0 +1,46 @@
+public class RadixSort {
+
+    public static void radixSort(int[] arr) {
+        int max = getMax(arr);
+        for (int exp = 1; max / exp > 0; exp *= 10) {
+            countSort(arr, exp);
+        }
+    }
+
+    private static int getMax(int[] arr) {
+        int max = arr[0];
+        for (int i = 1; i < arr.length; i++)
+            if (arr[i] > max)
+                max = arr[i];
+        return max;
+    }
+
+    private static void countSort(int[] arr, int exp) {
+        int n = arr.length;
+        int[] output = new int[n];
+        int[] count = new int[10];
+
+        for (int i = 0; i < n; i++)
+            count[(arr[i] / exp) % 10]++;
+
+        for (int i = 1; i < 10; i++)
+            count[i] += count[i - 1];
+
+        for (int i = n - 1; i >= 0; i--) {
+            int index = (arr[i] / exp) % 10;
+            output[count[index] - 1] = arr[i];
+            count[index]--;
+        }
+
+        for (int i = 0; i < n; i++)
+            arr[i] = output[i];
+    }
+
+    public static void main(String[] args) {
+        int[] arr = {170, 45, 75, 90, 802, 24, 2, 66};
+        radixSort(arr);
+        System.out.println("Sorted array:");
+        for (int num : arr)
+            System.out.print(num + " ");
+    }
+}