作业及其答案汇总图文稿

作业及其答案汇总

集团文件版本号：（M928-T898-M248-WU2669-I2896-DQ586-M1988）

一、类和对象基本概念

1) 写出下面程序的运行结果：

#include

class Apple {

private :

static int nTotalNumber;

public:

Apple()

{ nTotalNumber ++; }

~Apple( ) { nTotalNumber --; }

static void PrintTotal()

{ cout << nTotalNumber << endl; } };

int Apple::nTotalNumber = 0;

Apple Fun( const Apple & a )

{ a.PrintTotal(); return a ; }

int main () {

Apple * p = new Apple[4];

Fun( p[2]);

Apple p1, p2;

delete [] p;

p1.PrintTotal();

}

/*

4

1

*/

2) 写出下面程序的运行结果：

#include

class Sample{

public:

int v;

Sample() { };

Sample(int n):v(n) { };

Sample( Sample & x) { v = 2 + x.v ; } };

Sample PrintAndDouble( Sample o)

{

cout << o.v;

o.v = 2 * o.v;

return o;

}

int main()

{

Sample a(5);

Sample b = a;

Sample c = PrintAndDouble( b );

cout << endl;

cout << c.v << endl;

Sample d;

d = a;

cout << d.v ;

}

/*

9

22

5

*/

3) 下面的程序输出结果是：

5

请填空补足程序。所填内容不允许包含分号。class A {

public:

int val;

A(____________ ){ val = n; };

___A &________ GetObj() {

return _* this_______;

}

};

main() {

A a;

cout <

a.GetObj() = 5;

cout << a.val << endl;

}

/*

int n =0

A &

* this

*/

4) 下面程序的输出是：

3+4i

5+6i

请补足Complex类的成员函数。不能增加成员变量。#include

#include

using namespace std;

class Complex {

private:

double r,i;

public:

void Print() {

cout << r << "+" << i << "i" << endl;

}

};

int main()

{

Complex a;

a = "3+4i";

a.Print();

a = "5+6i";

a.Print();

}

/*

Complex() { };

Complex( char * s) {

r = s[0] - '0';

i = s[2] - '0';

}

*/

5) 下面程序的输出是：

10

请补足Sample类的成员函数。不能增加成员变量。#include

class Sample{

public:

int v;

Sample(int n):v(n) { };

};

int main()

{

Sample a(5);

Sample b = a;

cout << b.v ;

}

/*

Sample( Sample & x) { v = 2 * x.v ; }

*/

6)下面程序的输出是：

This

Hello

请补足MyString类的成员函数。不能增加成员变量。

#include

#include

class MyString{

char * p;

public:

MyString( char * s ) {

p = new char[strlen(s)+1];

strcpy(p,s);

}

~MyString() { delete [] p;}

const char * c_str() { return p;}

};

int main()

{

MyString s1("This"), s2 =s1;

s2.Copy ( "Hello");

cout << s1.c_str () << endl << s2.c_str () ; }

/*

void Copy( char * s) {