Template习题
//
//因为这次公司培训机制改变为先发布题目，由学员看书做题，再由教员专向辅导。
//因此这次没有准备讲义，只把题目贴上来，朋友们也可以练练手，过几天把部分答案上传。
//本套题分为四个难度：BASE, ADVANCED, EXPLORATION, FUN. 思考难度指数分别大概是
//2，5，7，9（满分10）。其中BASE和ADVANCED是要求学员一定要做的。EXPLORATION
//是探索题目，FUN是探索题目做完后还有余力的一些很有意思有嚼头的题目。
//
//PS:自我感觉题目总体难度有些高，不知道学员能不能坚持下来...
//这里想要放一个目录链接到一下各个section的，但是不知道怎么做，有朋友知道的能说说吗？
BASE:
1． write the output.
template<class Type>void Func(Type &x , Type &y)
{
Type a=x; x=y; y=a;
}#include <iostream>using namespace std;int main(){ int a = 12; int b = 24; Func(a,b); cout<<"a:"<<a<<" "<<"b:"<<b<<endl;}2． With the function Template:
template<int size , class T >void Show(T *d){ for( int j=0;j<size;j++) cout<<d[j]<<' ';}What is the template function prototype invoked by Show<10>("abcdefghijklmn")? What's the output?
3. the program's output is not right, please correct the following program with right semantics:
template<class T>T maxEx(T a,T b){ return (a > b) ? a : b;}int main(){ int nFirst = 10; int nSecond = 16; cout<<maxEx(nFirst, nSecond)<<endl; //should be 16 char *c1 = "a"; char *c2 = "zoo"; char *c3 = "ZOO"; char *c4 = "A"; cout<<maxEx(c1,c2)<<endl; //should be zoo cout<<maxEx(c3,c4)<<endl; //should be ZOO return 0;} 4.write the output of the following code.
template <class T> void f(T) // (d){ cout<<"d"<<endl;}template <class T> void f(int, T, double) // (e){ cout<<"e"<<endl;}template <class T> void f(T*) // (f){ cout<<"f"<<endl;}template <> void f<double> (double) // (g){ cout<<"g"<<endl;}void f(double) // (h){ cout<<"h"<<endl;}int main(){ bool b = true; int i = 1; double d = 3.14; f(b); f(i,42,d) ; f(&i) ; f(d); return 0;}5.Case:
template <class Type> class TwoNum{private: Type a; Type b;public:
TwoNum(){}
TwoNum() TwoNum(Type aa , Type bb); int Compare(); //比较a 和b的大小 Type Max() // 求a 和b的最大值 { return (a>b)?a:b; 
} Type Min() // 求a 和b的最小值 { return (a>b)?b:a; } void Setab(Type& aa , Type& bb) { a=aa; b=bb; } Type geta() { return a; } Type getb() { return b; }};template<class Type>TwoNum<Type>::TwoNum(Type aa ,Type bb) : a(aa), b(bb){ ;}template<class Type>int TwoNum<Type>::Compare(){ if(a>b) return 1; else if(a==b) return 0; else return -1;} #include <iostream.h>void main(){ TwoNum<int> x(4,8); cout<<x.Compare()<<’ ‘<<x.Max()<<’ ‘<<x.Min()<<endl; char ch=’x’; TwoNum<char> y(ch,’x’); cout<<y.Compare()<<’ ‘<<y.Max()<<’ ‘<<y.Min()<<endl;}Please write the output：
6．Which of the following templates are illegal? Why?
(1)
template <class Type>class Container1;template <class Type, int size>class Container1;template <class Type>void Container1(Type t);template <class Type, int size>void Container1(Type t);(2)
template <class T,U,class V>class Container2;(3)
template<typename myT, class myT>class Container3;(4)
template<class Type, int *ptr)class Container4;template<class Type, int * pi)class Container4;(5)
template <class Type, int val = 0>class Container6;7．correct the class CList declaration (No need to implement the members.)
template <class elementType>class ListItem;template<class elemType>class CList{public: CList(): front(NULL), end(NULL); CList (const List &); ~CList(); void insert(ListItem<elemType> *ptr, elemType<elemType> value); int remove(elemType<elemType> value); size_t size( ) { return _size; }private: ListItem<elemType> *front; ListItem<elemType> *end;};8.write the output for overload class template
template <class T> class mvector // (a){public: void f() { cout<<"a"<<endl; }};template <class T> class mvector<T*> // (b){ T t;public: void f() { t = 0; cout<<"b"<<endl; }}; template <> class mvector <void*> // (c){public: void f() { cout<<"c"<<endl; }};int main(){ mvector<void*> vpm; mvector<int*> ipm; mvector<int> im; vpm.f(); ipm.f(); im.f();}
ADVANCED:
1．Write a class template CVar<typename> which has following methods:
Operator + (CVar<typename>& ) //plus Operator –(CVar<typename>& ) //division Operator =(CVar<typename>& ) //assign Operator ==(CVar<typename>& ) //equal Operator typename() //cast Output(); //output it’s data;And other necessary members.
2. Write some global function template:
Operator +( CVar<Typename>& , CVar<Typename>&) Operator -( CVar<Typename>& , CVar<Typename>&)You can try to comment CVar class operator +/- to test whether your global function is enable.
3. Write a specialized template class CVar<char*> and CVar<bool>.
//Note: Using your semantics to implement the algorithm.
// such as : CVar<char*1> + CVar<char*2> : strcat();
// CVar<char*1> - CVar<char*2> : find all char*2 and delete them in char*1.
// CVar<bool> + CVar<bool> : &
// CVar<bool> - CVar<bool> : ^
4. Write a template function my_sort as following:
template<typename Type> Void my_sort(Type* array, size_t size);//NOTE:
//* Maybe you have to implement another 2 function templates:
template<typename Type> bool my_max(Type& lhs, Type& rhs); template<typename Type> Void my_swap(Type& lhs, Type& rhs);//* you can decide your concrete sort algorithm.
EXPLORATION:
1． Design a template queue class and implement the following members:
(1) method void add(Type elem). //add an element to tail.
(2) method Type remove(). //remove element from head, and return the element.
(3) method Type head(). //return the head value of queue.
(4) method void clear(). //clear all queue.
(5) method bool is_empty(). //indicate whether the queue is empty.
(6) method size_t count(). //return the count.
(7) nested class Iterator to traverse the queue.
(8) method operator+=(Type elem). //The same to add();
(9) method operator--(). //The same to remove();
(10) method Iterator begin(). //Return the begin of the queue.
(11) method Iterator end(). //Return the end of the queue.
Besides, define an global overload operator:
operator<<;
to directly output all the values of queue item.
the following is the test of your queue：
#include <iostream.h>#include "queue.h"using namespace std;void main(){ Queue<int> iq(10); for(int i=0; i < 10; i++) iq.add(i*5); iq--; iq += 50; if (!iq.is_empty()) cout << "Removed : " << iq.remove() << " Current Head : " << iq.head(); cout << endl; if (!iq.is_empty()) cout << iq; Queue<int>::Iterator iQueue; for(iQueue = iq.begin(); iQueue != iq.end(); iQueue++) { cout << (*iQueue)<<" "; } cout << endl; iq.clear(); cout << iq;}The ourput is：
Removed : 5 Current Head : 10
There are 9 queue items: < 10 15 20 25 30 35 40 45 50 >
10 15 20 25 30 35 40 45 50
There are 0 queue items: < >
2.design a class template CHash which algorithm is besed on buckets:
template< typename Key, typename Value >
class CHash{public: class Iterator { } CHash( const size_t nMax, ULONG ( *hashFunc )( const Key tKey ), bool bAutoSize = false ); CHash( const CHash& hash ); ~CHash(); CHash& operator= ( const CHash<Key, Value>& hash ); operator[]; Iterator begin(); Iterator end(); size_t size(); void insert( const Key tKey, Value& rValue ); void clear();}
FUN:
1.Write the output of the following code.
#include <IOSTREAM>using std::cout;using std::endl;template<int N>class CalculateCycle{public: enum { count = CalculateCycle< N % 2 ? (N * 3 + 1) : (N / 2) >::count + 1 };};template <>class CalculateCycle<1>{public: enum { count = 1 };};int main(){ const int iNo = 22; cout << "Cycle length of " << iNo << " is = " << CalculateCycle<iNo>::count << endl; return 0;}2.The following is a smart list. Please add other necessary implements to make it work.
#include <iostream>template<typename T>class CListTemplate{public: T* left; T* right; int elem;};class CMyList : public CListTemplate<CMyList>{public: size_t size;};template<class T>class CList : public T{public: T* Head;};int main(){ CList<CMyList> my_List; //my_List.left->left->right->elem = 10; return 0;}
