hdu 2051 Bitset （java）

问题：
之前做过类似题，但这次仍然不能解决相关问题。

字符串倒过来输：StringBuffer str=new StringBuffer(s); s=str.reverse().toString()

Bitset

Time Limit: 1000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 15548    Accepted Submission(s): 11804

Problem Description

Give you a number on base ten,you should output it on base two.(0 < n < 1000)

 

Input

For each case there is a postive number n on base ten, end of file.

 

Output

For each case output a number on base two.

 

Sample Input

123

 

Sample Output

11011

代码：

import java.util.*;public class Main{public static void main(String args[]){Scanner cin=new Scanner(System.in);while(cin.hasNext()){int n=cin.nextInt();String s="";while(n!=0){s=s+(n%2);n=n/2;}StringBuffer str=new StringBuffer(s); s=str.reverse().toString();System.out.println(str);}}}