数字按位倒转

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n个数，将其中的偶数的二进制反转
比如，输入1 6 5
6是偶数，二进制110，翻转后011，代表3，最终输出1 3 5
输入描述：
输入包含多组测试数据
对于每一组测试数据：
N——输入的字数
N个数：a0,a1,a2……,an-1
保证：
1<=N<=3000,0<=ai<=INT_MAX
输出描述：
对于每个数组，输出N个整数
输入例子：
5
1 3 10 6 7
6
26 52 31 45 82 34
输出例子：
1 3 5 3 7
11 11 31 45 37 17
解决方案有两种：
1.转化成2进制字符串然后倒转字符数组

import java.util.Scanner;/** * Created by Feng on 2016/6/21. */public class Main {    public static void main(String[] args) {        Scanner scanner = new Scanner(System.in);        while(scanner.hasNext()){            int n = scanner.nextInt();            int src[]  = new int[n];            for (int i = 0; i < n; i++) {                src[i] = scanner.nextInt();            }            for (int i = 0; i < n; i++) {                if((src[i]&1)==0){                    src[i] = Integer.parseInt(reve(Integer.toBinaryString(src[i])),2);                }            }            for (int i = 0; i <n ; i++) {                System.out.print(src[i] + " ");            }            System.out.println();        }    }    public static String reve(String s){        char[] src = s.toCharArray();        for (int i = 0; i <src.length/2 ; i++) {            char temp = src[i];            src[i] = src[src.length-i-1];            src[src.length-i-1] = temp;        }        return new String(src);    }}

2.按位运算

import java.util.Scanner;/** * Created by Feng on 2016/6/21. */public class Main {    public static void main(String[] args) {        Scanner scanner = new Scanner(System.in);        while(scanner.hasNext()){            int n = scanner.nextInt();            int src[]  = new int[n];            for (int i = 0; i < n; i++) {                src[i] = scanner.nextInt();            }           for (int i = 0; i < n; i++) {                if((src[i]&1)==0){                    int temp = src[i];                    while((temp&1)==0) temp = temp>>1;                    src[i] = 1;                    temp = temp>>1;                    while(temp>0){                        src[i] = src[i]<<1;                        if((temp&1)==0){                        }else{                            src[i]+=1;                        }                        temp = temp>>1;                    }                }            }            for (int i = 0; i <n ; i++) {                System.out.print(src[i] + " ");            }            System.out.println();        }    }}

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