题目地址：https://leetcode.com/problems/add-binary/description/
Given two binary strings, return their sum (also a binary string).
The input strings are both non-empty and contains only characters 1 or 0.
Example 1:
代码语言：javascript复制Input: a = "11", b = "1"
Output: "100"Example 2:
代码语言：javascript复制Input: a = "1010", b = "1011"
Output: "10101"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:
代码语言：javascript复制输入: a = "11", b = "1"
输出: "100"示例 2:
代码语言：javascript复制输入: a = "1010", b = "1011"
输出: "10101"class Solution {
public String addBinary(String a, String b) {
int i = a.length() - 1, j = b.length() - 1;
Stack<String> stack = new Stack<String>();
int jin = 0, num_a, num_b;
while (i >= 0 && j >= 0){
num_a = a.charAt(i--) == '0' ? 0 : 1;
num_b = b.charAt(j--) == '0' ? 0 : 1;
int temp = num_a num_b jin;
stack.push(temp % 2 == 0 ? "0" : "1");
jin = temp >> 1;
}
while (i >= 0) {
num_a = a.charAt(i--) == '0' ? 0 : 1;
int temp;
if (jin != 0) {
temp = num_a jin;
} else {
temp = num_a;
}
stack.push(temp % 2 == 0 ? "0" : "1");
jin = temp >> 1;
}
while (j >= 0) {
num_b = b.charAt(j--) == '0' ? 0 : 1;
int temp;
if (jin != 0) {
temp = num_b jin;
} else {
temp = num_b;
}
stack.push(temp % 2 == 0 ? "0" : "1");
jin = temp >> 1;
}
if (jin != 0) {
stack.push("1");
}
StringBuilder str = new StringBuilder();
while (!stack.isEmpty()) {
str.append(stack.pop());
}
return str.toString();
}
}
写了半天发现评论区的一位大佬直接用BigInteger解决了，感觉智商被碾压。。。，贴上代码
代码语言：javascript复制import java.math.*;
class Solution {
public String addBinary(String a, String b) {
return (new BigInteger(a, 2).add(new BigInteger(b, 2))).toString(2);
}
}
