LeetCode：537. Complex Number Multiplication

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.

1. 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.

这一道题重点就在于如何把a和b中的实虚部提取出来。

AC：

class Solution(object):    def complexNumberMultiply(self, a, b):        """        :type a: str        :type b: str        :rtype: str        """        a1, a2 = map(int, a[:-1].split('+'))        b1, b2 = map(int, b[:-1].split('+'))        return '%d+%di' % (a1 * b1 - a2 * b2, a1 * b2 + a2 * b1)