leetcode67. 二进制求和

妖狐艹你老母 2021-11-02 08:06 283阅读 0赞

**题目：**

给定两个二进制字符串，返回他们的和（用二进制表示）。

输入为非空字符串且只包含数字 1 和 0。

**示例 1:**

输入: a = "11", b = "1"  
　　输出: "100"  
**示例 2:**

输入: a = "1010", b = "1011"  
　　输出: "10101"

来源：[力扣（LeetCode）][LeetCode]

**解答：**

1 class Solution:
    2     def addBinary(self, a: str, b: str) -> str:
    3         return bin(int(a, 2) + int(b, 2))[2:]

1 class Solution:
     2     """
     3         作者：QQqun902025048
     4         链接：https://leetcode-cn.com/problems/two-sum/solution/python-1xing-nei-zhi-han-shu-fei-nei-zhi-jie-fa-by/
     5     """
     6     def addBinary(self, a: str, b: str) -> str:
     7         r, p = '', 0
     8         d = len(b) - len(a)
     9         a = '0' * d + a
    10         b = '0' * -d + b   # '0' * -d = ''
    11         for i, j in zip(a[::-1], b[::-1]):
    12             s = int(i) + int(j) + p
    13             r = str(s % 2) + r
    14             p = s // 2
    15         return '1' + r if p else r

--------------------

1 class Solution:
     2     def addBinary(self, a: str, b: str) -> str:
     3         _sum = ''
     4         c = 0
     5         d = len(a) - len(b)
     6         a = '0' * -d + a
     7         b = '0' * d + b
     8         for i in range(len(a) - 1, -1, -1):
     9             s = int(a[i]) + int(b[i]) + c
    10             if s == 2:
    11                 s = 0
    12                 c = 1
    13             elif s == 3:
    14                 s = 1
    15                 c = 1
    16             else:
    17                 c = 0
    18             _sum = str(s) + _sum
    19         
    20         if c == 1:
    21             _sum = '1' + _sum
    22         return _sum

转载于:https://www.cnblogs.com/catyuang/p/11178837.html

[LeetCode]: https://leetcode-cn.com/problems/add-binary