复数乘法
题目描述
思路
模拟
对于给定的两个复数num1和num2，首先分别得到两个复数的实部和虚部，然后计算两个复数的乘法。用real1和imag1分别表示num1的实部和虚部，用real2,和imag2分别表示num2的实部和虚部，则乘法计算结果为
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i
(real1+imag1*i) * (real2+imag2*i) = (real1*real2-imag1*imag2) + (real1*imag2+real2*imag1) * i
(real1+imag1∗i)∗(real2+imag2∗i)=(real1∗real2−imag1∗imag2)+(real1∗imag2+real2∗imag1)∗i
得到乘积后，将乘积转为字符串形式返回。
Python实现
class Solution:
def complexNumberMultiply(self, num1: str, num2: str) -> str:
real1, imag1 = map(int, num1[:-1].split('+'))
real2, imag2 = map(int, num2[:-1].split('+'))
return f'{real1*real2-imag1*imag2}+{real1*imag2+imag1*real2}i'
Java实现
class Solution {
public String complexNumberMultiply(String num1, String num2) {
String[] complex1 = num1.split("\\+|i");
String[] complex2 = num2.split("\\+|i");
int real1 = Integer.parseInt(complex1[0]), imag1 = Integer.parseInt(complex1[1]);
int real2 = Integer.parseInt(complex2[0]), imag2 = Integer.parseInt(complex2[1]);
return String.format("%d+%di", real1*real2-imag1*imag2, real1*imag2+real2*imag1);
}
}