LeetCode Add Binary

Given two binary strings, return their sum (also a binary string).

For example,a ="11"b ="1"Return"100".

题意：二进制的加法。

思路：跟大数加法差不多。

class Solution {public:string addBinary(string a, string b) {stack<int> s;int na = a.size() – 1;int nb = b.size() – 1;int c = 0;while (na > -1 || nb > -1) {int va = 0;if (na > -1) {va = a[na] – '0';na–;}int vb = 0;if (nb > -1) {vb = b[nb] – '0';nb–;}int tmp = va + vb + c;c = tmp / 2;s.push(tmp % 2);}if (c != 0) s.push(c);string ans;while (!s.empty()) {ans.push_back(s.top()+'0');s.pop();}return ans;}};

，其实你已经错过了旅行的意义。