北航软件学院研究生一级工程实践2004届考试试题+答案(2)

异质链表中增加数据的操作可用函数模板来实现，如例2.4所示。 例2.4

template hetero_node* push(T const &v, N *n) {

return new hetero_node(v, n); }

从异质链表中删除链表首数据的函数如例2.5所示。 例2.5

template N* pop(hetero_node *head) { N *next = head->next; delete head; return next; }

10. 简述采用socket通信时服务器端和客户端的主要工作过程。（5分）

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二、 读程序写结果，并简述产生各输出结果的原因（每小题4分，共20分） 1．#include

int main(int argc, char* argv[]) {

char str1[] = \ char str2[] = \

const char str3[] = \ const char str4[] = \

const char* str5 = \指向常量的指针 const char* str6 = \

cout << ( str1==str2 ) << endl; 0 cout << ( str3==str4 ) << endl; 0

cout << ( str5==str6 ) << endl; 1比较的是地址 }

2. #include

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class Point {

public: Point(double i, double j) { x=i; y=j; } virtual double Area() const { return x*y; } private: double x, y; };

class Rectangle:public Point {

public: Rectangle(double i, double j, double k, double l); virtual double Area() const { return w*h; } private: double w, h; };

Rectangle::Rectangle(double i, double j, double k, double l):Point(i, j) { w=k; h=l; }

void fun(Point &s) { cout<

void main() { Rectangle rec(1.0, 2.0, 3.0, 4.0); Point *pt;

fun(rec);

pt = (Point *)&rec; fun(*pt); } 12 12

3. #include

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class Test;

void fun1(Test t); Test fun2();

class Test {

public:

Test(int n=1) {val=n; cout<<\ }

Test(const Test& t) {val=t.val; cout<<\Test& operator = (Test& t) {

val=t.val;

cout<<\return *this;

} private:

int val; };

void main() {

Test t1(1); Test t2=t1; Test t3;

t3=t1; fun1(t2); t3=fun2(); }

void fun1(Test t){}

Test fun2() {

Test t; return t; }

4. # include

struct Point { int *x, *y;

};

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void move ( Point &q ) {

--*q.x; ++*q.y; }

int main() { Point p; int a = 5, b = -12, t; p.x = &a; p.y = &b; move( p ); t = a; a = b++; b = t++; cout << “p.x = “ << *p.x << endl; cout << “p.y = “ << *p.y << endl; return 0; }

p.x =-11

p.y =4

5. #include

#include

class string {

public: string(char *s);

string(string &s1); string(int size=80);

~string() { delete sptr; } int getlen() { return length; }

void print() { cout<

};

string::string(char *s) { length = strlen(s);

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