LeetCode 67. Add Binary

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

For example,
a = “11”
b = “1”
Return “100”.

class Solution {
public:
    string addBinary(string a, string b) {
        string s;
        int lena = a.length() - 1;
        int lenb = b.length() - 1;
        int temp = 0;
        char c;
        while(lena >= 0 && lenb >= 0) {
            c = (a[lena] - '0') + (b[lenb] - '0') + temp + '0';
            temp = 0;
            if((c - '0') >= 2) {
                temp = 1;
                c = c - 2;
            }
            s = c + s;
            lena--;
            lenb--;
        }
        while(lena >= 0) {
            c = (a[lena] - '0') + temp + '0';
            temp = 0;
            if((c - '0') >= 2) {
                temp = 1;
                c = c - 2;
            }
            s = c + s;
            lena--;
        }
        while(lenb >= 0) {
            c =(b[lenb] - '0') + temp + '0';
            temp = 0;
            if((c - '0') >= 2) {
                temp = 1;
                c = c - 2;
            }
            s = c + s;
            lenb--;
        }
        if(temp == 1) {
            s = '1' + s;
        }
        return s;
    }
};

class Solution {

public:

string addBinary(string a, string b) {

string s;

int lena = a.length() - 1;

int lenb = b.length() - 1;

int temp = 0;

char c;

while(lena >= 0 && lenb >= 0) {

c = (a[lena] - '0') + (b[lenb] - '0') + temp + '0';

temp = 0;

if((c - '0') >= 2) {

temp = 1;

c = c - 2;

}

s = c + s;

lena--;

lenb--;

}

while(lena >= 0) {

c = (a[lena] - '0') + temp + '0';

temp = 0;

if((c - '0') >= 2) {

temp = 1;

c = c - 2;

}

s = c + s;

lena--;

}

while(lenb >= 0) {

c =(b[lenb] - '0') + temp + '0';

temp = 0;

if((c - '0') >= 2) {

temp = 1;

c = c - 2;

}

s = c + s;

lenb--;

}

if(temp == 1) {

s = '1' + s;

}

return s;

}

};

❤ 点击这里 -> 订阅《PAT | 蓝桥 | LeetCode学习路径 & 刷题经验》by 柳婼

❤ 点击这里 -> 订阅《从放弃C语言到使用C++刷算法的简明教程》by 柳婼

❤ 点击这里 -> 订阅PAT甲级乙级、蓝桥杯、GPLT天梯赛、LeetCode题解离线版