Careercup - Facebook面试题 - 4892713614835712

2014-05-02 09:54

题目链接

原题：

You have two numbers decomposed in binary representation, write a function that sums them and returns the result. 

Input: ,
Output: 

题目：做二进制加法。

解法：字符串就行了，不需要额外开辟数组。string对象本身就是一个vector，也就是一个数组喽。

代码：

 // http://www.careercup.com/question?id=4892713614835712
 #include <iostream>
 #include <string>
 using namespace std;

 string binaryAdd(string &a, string &b)
 {
     if (a.length() > b.length()) {
         return binaryAdd(b, a);
     }

     string c;
     int carry;
     int na, nb;
     int bita, bitb;
     int i;

     reverse(a.begin(), a.end());
     reverse(b.begin(), b.end());

     na = (int)a.length();
     nb = (int)b.length();
     carry = ;
     for (i = ; i < nb; ++i) {
         bita = i < na ? a[i] - '' : ;
         bitb = b[i] - '';
         c.push_back((bita ^ bitb ^ carry) + '');
         carry = (bita + bitb + carry) > ;
     }
     if (carry) {
         c.push_back('');
     }
     reverse(c.begin(), c.end());

     return c;
 }

 int main()
 {
     string a, b, c;

     while (cin >> a >> b) {
         c = binaryAdd(a, b);
         cout << c << endl;
     }

     return ;
 }