#include<iostream> using namespace std; class Xx { private : int num; public : Xx(int x) {num =x;} //构造函数 ~Xx(){cout<<" dst "<<num<<endl;}//析构函数 }; int main() { Xx w(5); //语句1 cout<<"Exit main"<< endl; //语句2 return 0; }修改错误

这段代码有一个错误，构造函数的声明格式不正确，应该是类名后面加上一对括号，而不是加上参数列表。以下是修改后的代码：

#include<iostream> 
using namespace std; 

class Xx { 
private: 
    int num; 
public: 
    Xx(int x) {num =x;} //构造函数 
    ~Xx(){cout<<" dst "<<num<<endl;} //析构函数 
}; 

int main() { 
    Xx w(5); //语句1 
    cout<<"Exit main"<< endl; //语句2 
    return 0; 
}

这段代码创建了一个名为 `w` 的 `Xx` 对象，并将参数 `5` 传递给构造函数。当 `main` 函数结束时，`w` 对象将被销毁，析构函数将被调用，输出 `" dst 5"`。最后输出 `"Exit main"`。

相关问题

请补足Fraction类的成员函数（不能加数据成员） #include <iostream> #include <cstring> #include <cstdlib> using namespace std; class Fraction { private: int _s, _m; public: void Print() { cout << _s << "/" << _m << endl; } // 在此处补充你的代码 }; int main() { Fraction a; a = "3/5"; a.Print(); a = "48/-72"; a.Print(); return 0; }

下面是补全后的Fraction类的成员函数：

class Fraction
{
private:
    int _s, _m;

public:
    void Print() { cout << _s << "/" << _m << endl; }

    Fraction& operator=(const char* str) {
        int len = strlen(str);
        int pos = 0;
        int numerator = 0, denominator = 0;
        bool is_negative = false;

        // 判断是否为负数
        if (str[pos] == '-') {
            is_negative = true;
            ++pos;
        }

        // 读取分子
        while (pos < len && str[pos] != '/') {
            numerator = numerator * 10 + str[pos] - '0';
            ++pos;
        }

        // 跳过 '/' 符号
        ++pos;

        // 读取分母
        while (pos < len) {
            denominator = denominator * 10 + str[pos] - '0';
            ++pos;
        }

        // 判断分母是否为 0
        if (denominator == 0) {
            cout << "Error: denominator cannot be zero!" << endl;
            exit(1);
        }

        // 处理负数情况
        if (is_negative) {
            numerator = -numerator;
        }

        // 约分
        int gcd_num = gcd(abs(numerator), denominator);
        _s = numerator / gcd_num;
        _m = denominator / gcd_num;

        return *this;
    }

    // 辗转相除法求最大公约数
    int gcd(int a, int b) {
        if (b == 0) {
            return a;
        }
        return gcd(b, a % b);
    }
};

在上面的代码中，我们重载了赋值运算符 `operator=`，使得可以直接用字符串对一个 Fraction 对象进行赋值。在 `operator=` 中，我们首先处理了字符串是否为负数的情况，然后分别读取了分子和分母，并判断了分母是否为 0。接着，我们对读入的分数进行约分，最后将约分后的结果存储到 `_s` 和 `_m` 中。为了实现约分，我们使用了辗转相除法求最大公约数。

#include <iostream> #include <string> #include <iomanip> using namespace std; class house{ private: string location; int num_of_rooms; int year_built; public: house(); house(string,int,int); void set_location(string); string get_location(); void set_num_of_rooms(int); int get_num_of_rooms(); void set_year_built(int); int get_year_built(); void print_house_details(); };

This is a class declaration for a `house` class with some private member variables and public member functions. Here is an example implementation for the `house_impl.cpp` file:

#include "house.h"

// Default constructor
house::house() {
    location = "";
    num_of_rooms = 0;
    year_built = 0;
}

// Parameterized constructor
house::house(string loc, int num, int year) {
    location = loc;
    num_of_rooms = num;
    year_built = year;
}

// Setter and getter functions for location
void house::set_location(string loc) {
    location = loc;
}

string house::get_location() {
    return location;
}

// Setter and getter functions for number of rooms
void house::set_num_of_rooms(int num) {
    num_of_rooms = num;
}

int house::get_num_of_rooms() {
    return num_of_rooms;
}

// Setter and getter functions for year built
void house::set_year_built(int year) {
    year_built = year;
}

int house::get_year_built() {
    return year_built;
}

// Function to print house details
void house::print_house_details() {
    cout << "Location: " << location << endl;
    cout << "Number of rooms: " << num_of_rooms << endl;
    cout << "Year built: " << year_built << endl;
}

Note that the implementation file should include the header file `house.h` which contains the declaration of the `house` class.