Return location -- 8 Kyu

原题

https://www.codewars.com/kata/return-location

题目

You are given a class named Person with a method named location, which should return the 3D location of the given person.

Can you find the bug?

class Person
{
    public:
        Person(int x, int y, int z)
            : m_x(x), m_y(y), m_z(z)
        {
        }
        
        void location(int x, int y, int z)
        {
            x = m_x;
            y = m_y;
            z = m_z;
        }
        
    private:
        int m_x;
        int m_y;
        int m_z;
};

分析

这是一个程序排错问题，考察的参数引用传递。

参考答案

class Person
{
    public:
        Person(int x, int y, int z)
            : m_x(x), m_y(y), m_z(z)
        {
        }
        
        void location(int& x, int& y, int& z)
        {
            x = m_x;
            y = m_y;
            z = m_z;
        }
        
    private:
        int m_x;
        int m_y;
        int m_z;
};

说明

值传递和引用传递使用方法相同，但是参数定义方式不同，作用也不同。

其它