AddBinary

 1 package com.rust.TestString;
 2 
 3 public class AddBinary {
 4     public static String addBinary(String a, String b) {
 5         int alen = a.length() - 1;
 6         int blen = b.length() - 1;
 7         int carry = 0;
 8         String res = "";
 9         while (alen >=0 || blen >= 0 || carry == 1){
10             int delta = (alen < 0)? 0 : a.charAt(alen--) - ‘0‘;/* 得到int */
11             int beta = (blen < 0)? 0 : b.charAt(blen--) - ‘0‘;
12             res = (char)(‘0‘ + delta ^ beta ^ carry) + res;/* 异或处理得到当前位 */
13             carry = (delta + beta + carry) >> 1;/* 移位处理得到进位 */
14         }
15         return res;
16     }
17 
18     public static void main(String args[]){
19         String text = "0101010";
20         String atext =    "111";
21         String btext =    "010";
22         System.out.println(addBinary(atext, text));
23         System.out.println(addBinary(atext, btext));
24         System.out.println(addBinary(btext, text));
25     }
26 }