基数排序

import java.util.Arrays;public class RadixSort {    //基于计数排序的基数排序算法    public static void radixSort(int[] array,int radix, int digit) {        //array为待排序数组        //radix，代表基数，实际就是几个数字，那就是10喽        //digit代表排序元素的位数，实际意义是排序趟数                int length = array.length;        int[] res = new int[length];        int[] c = new int[radix];//radix就是10，因为0到9共10个数字        int divide = 1;//用于每次把数字缩小10倍                for (int i = 0; i < digit; i++) {                        res = Arrays.copyOf(array, length);            Arrays.fill(c, 0);                        for (int j = 0; j < length; j++) {                int tempKey = (res[j]/divide)%radix;                c[tempKey]++;            }                        for (int j = 1; j < radix; j++) {                c [j] = c[j] + c[j-1];            }                        for (int j=length-1; j>=0; j--) {                int tempKey = (res[j]/divide)%radix;                array[c[tempKey]-1] = res[j];                c[tempKey]--;            }            divide = divide * radix;                        }    }        public static int countDigit(int[] array) {        int max = array[0];        for (int i = 1; i < array.length; i++) {            if (array[i] > max) {                max = array[i];            }        }                int time = 0;       /* while (max > 0) {            max /= 10;            time++;        }*/int time=(int)Math.rint(Math.log10(max));//向上去整        return time;    }        public static void main(String[] args) {        int[] array = {3,2,3,2,5,333,45566,2345678,78,990,12,432,56};        int time = countDigit(array);        //System.out.println(time);        radixSort(array,10,time);        for (int i = 0; i < array.length; i++) {            System.out.print("  " + array[i]);        }    }}