radix sort python tutorial code example

Example 1: radix sort pseudocode

Radix-Sort(A, d)
       for j = 1 to d do
            int count[10] = {0};
            for i = 0 to n do
                count[key of(A[i]) in pass j]++
            for k = 1 to 10 do
                count[k] = count[k] + count[k-1]
            for i = n-1 downto 0 do
                result[ count[key of(A[i])] ] = A[j]
                count[key of(A[i])]--
            for i=0 to n do
                A[i] = result[i]
       end for(j)
 end func

Example 2: radix sort pseudocode

import java.io.*; 
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 ]++; 
           // 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 ]--; 
        }
           for (i = 0; i < n; i++) 
                   arr[i] = output[i]; 
    } 
   static void radixsort(int arr[], int n) 
       { // Find the maximum number to know number of digits 
           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); 
    } 
} 
JavaCopy

Tags:

Cpp Example