c++二级考试试题1--答案.doc

试题1答案1、/ proj1.cpp#include using namespace std;class MyClass public: MyClass(int len) array = new intlen; arraySize = len; for(int i = 0; i arraySize; i+) arrayi = i+1; MyClass() / ERROR *found* delete array; void Print() const for(int i = 0; i arraySize; i+)/ ERROR *found* cout arrayi ; cout endl; private: int *array; int arraySize;int main()/ ERROR *found* MyClass obj=10; obj.Print(); return 0;2、/ proj2.cpp#include using namespace std;const int MAXNUM = 100;class Set private: int num; / 元素个数 char setdataMAXNUM; / 字符数组，用于存储集合元素public: Set(char *s); / 构造函数，用字符串s构造一个集合对象 bool InSet(char c); / 判断一个字符c是否在集合中，若在，返回true，否则返回false void Print() const; / 输出集合中所有元素;Set:Set(char *s) num = 0; while (*s)/*found* if (!InSet(*s) / TODO: 添加代码，测试元素在集合中不存在/*found* setdatanum+ = *s ; / TODO: 添加一条语句，加入元素至集合中 s+; bool Set:InSet(char c)for (int i = 0; i num; i+)/*found* if (c = setdatai) / TODO: 添加代码，测试元素c是否与集合中某元素相同/*found* return true; / TODO: 添加一条语句，进行相应处理return false;void Set:Print() const cout Set elements: endl; for(int i = 0; i num; i+) cout setdatai ; cout endl;int main() char sMAXNUM; cin.getline(s, MAXNUM-1); / 从标准输入中读入一行 Set setobj(s); / 构造对象setobj setobj.Print(); / 显示对象setobj中内容 return 0;3、/ proj3.cpp#includeusing std:ostream;using std:cout;using std:endl;class MyVector /表示二维向量的类 double x; /X坐标值 double y; /Y坐标值public: MyVector(double i=0.0 , double j=0.0); /构造函数 MyVector operator+( MyVector j); /重载运算符+ friend MyVector operator-( MyVector i, MyVector j); /重载运算符- friend ostream& operator( ostream& os, MyVector v); /重载运算符;/*1* *found*MyVector:MyVector(double i , double j): x(i),y(j)MyVector MyVector:operator+( MyVector j) return MyVector(x+j.x, y+j.y);MyVector operator-( MyVector i, MyVector j)/*2* *found* return MyVector(i.x-j.x,i.y-j.y);ostream& operator( ostream& os, MyVector v) os ( v.x , v.y ) ; /输出向量v的坐标