Given two binary strings, return their sum (also a binary string).
For example,
a = "11"
b = "1"
Return "100"
.
一道二进制加法,思路还是很清晰的
最开始的想法是这样的,先reverse,然后加,搞一个temp存进位,好像就行了吧。。。走起。。。试试
果然还是代码量问题咩。。。搞了好久。。坑。。。
class Solution {
public:
string addBinary(string a, string b) {
string longStr = a.length() > b.length() ? a : b;
string shortStr = a.length() > b.length() ? b : a;
int flag = 0;
int i = shortStr.length() - 1;
int j = longStr.length() - 1;
for(;i >= 0;i--,j--)
{
if(shortStr[i] - '0' + longStr[j] - '0' + flag > 1)
{
longStr[j] = '0' + (shortStr[i] - '0' + longStr[j] - '0' + flag)%2;
flag = 1;
}
else
{
longStr[j] = '0' + (shortStr[i] - '0' + longStr[j] - '0' + flag)%2;
flag = 0;
}
}
for(;j >= 0;j--)
{
if(longStr[j] - '0' + flag > 1)
{
longStr[j] = '0' + (longStr[j] - '0' + flag)%2;
flag = 1;
}
else
{
longStr[j] = '0' + (longStr[j] - '0' + flag)%2;
flag = 0;
}
}
if(flag == 1)
{
longStr = '1' + longStr; //还是忘记了加法是连接
}
return longStr;
}
};