Radix sort

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// Radix sort Java implementation 
import java.io.*;
import java.util.*;

class Radix {

// A utility function to get maximum value in arr[]
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;
}

// A function to do counting sort of arr[] according to
// the digit represented by exp.
static void countSort(int arr[], int n, int exp) {
int output[] = new int[n]; // output array
int i;
int count[] = new int[10];
Arrays.fill(count, 0);

// Store count of occurrences in count[]
for (i = 0; i < n; i++)
count[(arr[i] / exp) % 10]++;

// Change count[i] so that count[i] now contains
// actual position of this digit in output[]
for (i = 1; i < 10; i++)
count[i] += count[i - 1];

// Build the output array
for (i = n - 1; i >= 0; i--) {
output[count[(arr[i] / exp) % 10] - 1] = arr[i];
count[(arr[i] / exp) % 10]--;
}

// Copy the output array to arr[], so that arr[] now
// contains sorted numbers according to curent digit
for (i = 0; i < n; i++)
arr[i] = output[i];
}

// The main function to that sorts arr[] of size n using
// Radix Sort
static void radixsort(int arr[], int n) {
// Find the maximum number to know number of digits
int m = getMax(arr, n);

// Do counting sort for every digit. Note that instead
// of passing digit number, exp is passed. exp is 10^i
// where i is current digit number
for (int exp = 1; m / exp > 0; exp *= 10)
countSort(arr, n, exp);
}

// A utility function to print an array
static void print(int arr[], int n) {
for (int i = 0; i < n; i++)
System.out.print(arr[i] + " ");
}

/* Driver function to check for above function */
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);
}
}
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