https://leetcode.com/problems/add-binary/

题目:

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

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

 

思路:

数组模拟加法操做,注意首位进一的情况。

 

 

class Solution {
public:
    string addBinary(string a, string b) {
        string c="",d="";
        if(a=="0"&&b=="0")
            return "0";
        int a_t=a.size(),b_t=b.size(),min_t=min(a_t,b_t),max_t=max(a_t,b_t);
        int tmp_a,tmp_b,jinyi=0;
        for(int i=0;i<max_t;i++){
            if(i<a_t)
                tmp_a=a[a_t-i-1]-'0';
            else
                tmp_a=0;
            if(i<b_t)    
                tmp_b=b[b_t-i-1]-'0';
            else
                tmp_b=0;
            c.push_back((tmp_a+tmp_b+jinyi)%2+'0');
            if(tmp_a+tmp_b+jinyi>=2)
                jinyi=1;
            else
                jinyi=0;
        }
        if(jinyi==1)
            c.push_back('1');
        for(int i=c.size()-1;i>=0;i--)
            d.push_back(c[i]);
        return d;
    }
};