JavaAlgorithms/Sorts/radixSort.java

import java.util.*;
 
class Radix {
 
    
    static int getMax(int arr[], int n)
    {
        int mx = arr[0];
        for (int i = 1; i < n; i++)
            if (arr[i] > mx)
                mx = arr[i];
        return mx;
    }
 
    static void countSort(int arr[], int n, int exp)
    {
        int output[] = new int[n];
        int i;
        int count[] = new int[10];
        Arrays.fill(count,0);
 
        for (i = 0; i < n; i++)
            count[ (arr[i]/exp)%10 ]++;
 
        for (i = 1; i < 10; i++)
            count[i] += count[i - 1];
 
        for (i = n - 1; i >= 0; i--)
        {
            output[count[ (arr[i]/exp)%10 ] - 1] = arr[i];
            count[ (arr[i]/exp)%10 ]--;
        }
 
        for (i = 0; i < n; i++)
            arr[i] = output[i];
    }
 
    static void radixsort(int arr[], int n)
    {

        int m = getMax(arr, n);
 

        for (int exp = 1; m/exp > 0; exp *= 10)
            countSort(arr, n, exp);
    }
 

    static void print(int arr[], int n)
    {
        for (int i=0; i<n; i++)
            System.out.print(arr[i]+" ");
    }
 


    public static void main (String[] args)
    {
        int arr[] = {170, 45, 75, 90, 802, 24, 2, 66};
        int n = arr.length;
        radixsort(arr, n);
        print(arr, n);
    }
}
// Written by James Mc Dermott(theycallmemac)