LeetCode 537. Complex Number Multiplication

题目链接：https://leetcode.com/problems/complex-number-multiplication/description/

Given two strings representing two complex numbers.

You need to return a string representing their multiplication. Note i2 = -1 according to the definition.

Example 1:

Input: "1+1i", "1+1i"
Output: "0+2i"
Explanation: (1 + i) * (1 + i) = 1 + i2 + 2 * i = 2i, and you need convert it to the form of 0+2i.

 

Example 2:

Input: "1+-1i", "1+-1i"
Output: "0+-2i"
Explanation: (1 - i) * (1 - i) = 1 + i2 - 2 * i = -2i, and you need convert it to the form of 0+-2i.

 

Note:

1. The input strings will not have extra blank.
2. The input strings will be given in the form of a+bi, where the integer a and b will both belong to the range of [-100, 100]. And the output should be also in this form.

题目解析：就是对stringstream的使用吧。

代码如下：0ms Accepted beating 100%

class Solution {
public:
    string complexNumberMultiply(string a, string b) {
        int areal, aimag, breal, bimag, real, imag; 
        char ch;
        stringstream astr(a), bstr(b);
        astr >> areal >> ch >> aimag >> ch; 
        bstr >> breal >> ch >> bimag >> ch;
        real = areal * breal - aimag * bimag;
        imag = breal * aimag + areal * bimag;
        return to_string(real) + "+" + to_string(imag) + "i";
    }
};