C++ 프로그래밍실습. Visual Studio Smart Computing Laboratory

Transcription

1 C++ 프로그래밍실습 Visual Studio 2015

2 Templates & STL Contents Exercise

3 Practice1 Templates & STL

4 Practice 1-1 Template Classes #include<iostream> using namespace std; template <typename T> class Point { private: T xpos, ypos; public: Point(T x =0,T y=0) :xpos(x), ypos(y){ void showposition() const { cout << '[' << xpos << "," << ypos << ']' << endl; ; int main() { Point<int> pos1(3, 4); pos1.showposition(); Execution Result: Point<double> pos2(2.4, 6.7); pos2.showposition(); Point<char> pos3('p', 'F ); spos3.showposition(); [3,4] [2.4,6.7] [P,F]

5 Practice 1-2 : Template Classes Class Parameters: int, char, X-type, Template Class Array<param> Instantiation Instantiation Class Array<int> Class Array<char> Class Array<X-type> Integer Array Character Array X-type Array

6 Practice 1-2 : Template Classes #include <iostream> #include <string> using namespace std; template<typename T> class Array { private: T* buf; int size; int capacity; public: Array(int cap = 100) : buf(0), size(0), capacity(cap) { buf = new T[capacity]; // 생성자는저장가능한최대원소의개수 (cap) 를인자로받아메모리생성 ~Array() { delete[] buf; // 생성한메모리제거 void Add(T data) { buf[size++] = data; //Array 객체에정수 (data) 를저장 ( 추가 ) T operator[] (int idx) const { return buf[idx]; //Array 객체의 idx 인텍스원소의값을반환 ; int GetSize() const { return size; // 객체의원소개수를반환

7 Practice 1-2 : Template Classes int main() { Array<int> arr; arr.add(10); arr.add(20); arr.add(30); for (int i = 0; i < arr.getsize(); i++) { cout << arr[i] << " "; cout << endl; Array<string> sarr; sarr.add("abc"); sarr.add("abc"); sarr.add("hello!"); for (int i = 0; i < sarr.getsize(); i++) { cout << sarr[i] << " "; cout << endl; Array<double> darr; darr.add(10.12); darr.add(20.12); darr.add(30.12); for (int i = 0; i < darr.getsize(); i++) { cout << darr[i] << " "; cout << endl; Execution Result: abc ABC Hello!

8 Practice 1-3 Vector vector<int>::const_iterator it; it = v.begin(); // initializes iterator for vector v while (it!= v.end()) { // is the iterator at the end? cout << *it << endl; // prints the element pointed by it it++; // increments the iterator // *** iterators are handled just like pointers

9 Practice 1-3 Vector #include <iostream> #include <vector> using namespace std; int main() { vector<int> v; // push_back : 벡터제일뒤에원소추가 v.push_back(1); v.push_back(2); v.push_back(3); v.push_back(4); v.push_back(5); // pop_back : 벡터제일뒤에원소삭제 v.pop_back(); cout << "vector front value : " << v.front() << endl; cout << "vector end value : " << v.back() << endl; // [i] and at(i) : i 번째원소반환 cout << "vector opeartor[] : " << v[3] << endl; cout << "vector at : " << v.at(3) << endl; // size : 벡터원소들의수 cout << "vector size : " << v.size() << endl;; // empty : 벡터가비어있으면 true 아니면 false cout << "Is it empty? : " << (v.empty()? "Yes" : "No") << endl; Execution Result: vector front value : 1 vector end value : 4 vector opeartor[] : 4 vector at : 4 vector size : 4 Is it empty? : No

10 N-1 Practice 1-4 Deque A deque is almost the same as a vector If we just replace vector with deque in the previous example, the output is exactly the same They just differ in their underlying implementation, in particular with respect to insertions and deletions A vector generally requires O(n) time for insertions and deletions, but O(1) time for insertions and deletions at the end Efficient for applications in which insertions and deletions are typically done at the end A deque requires O(1) time for insertions and deletions at the beginning or at the end Thus, it is efficient for applications in which insertions and deletions are typically done at both ends Note that a deque takes more time than a vector for insertions and deletions at the end due to using circular array mechanism Deque f r N-1 No shifting required for insertions and deletions at both ends, it maintains two pointers f and r for both ends in a circular fashion E.g.) front = (front + 1) % N, rear = (rear + 1) % N

11 Practice 1-4 Deque #include <iostream> #include <deque> using namespace std; int main() { deque<int> dq; dq.push_back(8); dq.push_back(9); dq.push_front(2); dq.push_front(1); dq.pop_front(); dq.pop_back(); for (unsigned i = 0; i < dq.size(); i++) { cout << dq[i] << " "; cout << endl; Execution Result: 2 8

12 Practice 1-5 List The list container is a bidirectional node list Implemented as a doubly linked list Node implementation includes Reference to an element Link to the previous node Link to the next node Special trailer and header nodes Header points to the beginning Trailer points to the end prev elem next node header begin end trailer elements

13 #include <iostream> #include <list> Practice 1-5 List using namespace std; int main() { list<int> l; // push_back : 리스트제일뒤에원소추가 l.push_back(5); l.push_back(6); l.push_back(7); l.push_back(8); l.push_back(9); l.push_back(10); // pop_back : 리스트제일뒤에원소삭제 l.pop_back(); // push_front : 리스트제일앞에원소추가 l.push_front(4); l.push_front(3); l.push_front(1); l.push_front(0); // pop_front : 리스트제일앞에원소삭제 l.pop_front(); cout << "list front value : " << l.front() << '\n ; cout << "list end value : " << l.back() << '\n ; // size : 리스트원소들의수 cout << "list size : " << l.size() << '\n ; // empty : 리스트가비어있다면 true 아니면 false cout << "Is it empty? : " << (l.empty()? "Yes" : "No") << '\n'; Execution Result: list front value : 1 list end value : 9 list size : 8 Is it empty? : No

14 Exercise 1. A wise man will make more opportunities than he finds * 위의문장을 STL 의 List 클래스를이용하여완성하시오 * 최종출력값은위의문장을뒤에서부터출력하시오.(Ex. sdnif eh esiw A) 2. STL 의 vector 클래스를이용하여작성한다. vector 객체를생성하고, 키보드로부터정수를입력받을때마다정수를 vector 에삽입하고지금까지입력된수와평균을출력하는프로그램을작성. 단, 0 을입력하면프로그램종료 ( 평균 avg 를구할때형변환해준후계산 )

15 Submit Teaching assistant: 장성수 Office: 신공학관 1216 호 ( 대학원 SCLab 연구실 ) pik1100@naver.com Title of the [2018][Practice#]_student# _ student _ name Ex) [2018][Practice11]_ _ 장성수 Create zip file. (C++ project folder) - 주의 : 메일양식이잘못될경우채점이되지않을수있음. 질문메일 : pik1100@naver.com : 장성수

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