奇数位按升序排序，偶数位按降序排序

import java.util.Scanner;public class Main{public static void main(String[] args){Scanner scan = new Scanner(System.in);while(scan.hasNext()){String str = scan.nextLine();sort(str);}scan.close();}private static void sort(String str){//去掉空格，保存数字int str_length = str.length();StringBuilder sb = new StringBuilder();for(int i = 0 ; i < str_length ; i++){if(str.charAt(i) != ' '){sb.append(str.charAt(i));}}char[] num = sb.toString().toCharArray();int length = num.length;int part_length = length / 2;//保存一半数字，按照奇数偶数保存char[] odd;char[] even;//偶数个数字if(length % 2 == 0){odd = new char[part_length]; even = new char[part_length];}else{//奇数个数字,多一个奇数odd = new char[part_length + 1];even = new char[part_length];}int index_odd = 0;int index_even = 0;for(int i = 0 ; i < length ; i++){if(i % 2 == 0){odd[index_odd++] = num[i];}else{even[index_even++] = num[i];}} ascendingSort(odd);//奇数位升序descendingSort(even);//偶数位降序for(int i = 0 ; i < index_even ; i++){if(i == 0)  System.out.print(odd[i] + " " + even[i]);else System.out.print(" " + odd[i] + " " + even[i]);}if(index_odd != index_even){System.out.println(" " +odd[index_odd - 1]);}}private static void ascendingSort(char[] data){int length = data.length;char temp = '*';for(int i = 0 ; i < length - 1 ; i++){for(int j = i + 1 ; j < length ; j++){if(data[i] > data[j]){temp = data[i];data[i] = data[j];data[j] = temp;}}}}private static void descendingSort(char[] data){int length = data.length;char temp = '*';for(int i = 0 ; i < length - 1 ; i++){for(int j = i + 1 ; j < length ; j++){if(data[i] < data[j]){temp = data[i];data[i] = data[j];data[j] = temp;}}}} }