https://oj.leetcode.com/problems/add-binary/
Given two binary strings, return their sum (also a binary string).
For example,
a = "11"
b = "1"
Return "100".
解题报告:二进制加法,分类为:Easy。没有任何算法,就是按照普通的方法计算即可。
一开始写了一个高低位reverse的,然后再从0到高位做加法,一直算到位数少的到头,然后如果有进位(carry)再对剩余的位数多的string做进位运算。
后来发现不用reverse也可以,直接从最高位向0位计算。AC代码如下:
public class Solution { public String addBinary(String a, String b) { StringBuffer result = new StringBuffer(""); int i = a.length() - 1; int j = b.length() - 1; int carry = 0; int index = 0; int acurrent = 0; int bcurrent = 0; for(;i>=0||j>=0;i--,j--) { acurrent = i>=0? a.charAt(i) - '0' : 0; bcurrent = j>=0? b.charAt(j) - '0' : 0; int current = (acurrent + bcurrent + carry)%2; carry = (acurrent + bcurrent + carry)/2; result = result.insert(0, current); } if(carry ==1) { result.insert(0, '1'); } return result.toString(); } }
原文:http://blog.csdn.net/worldwindjp/article/details/41593021