Problem B: 還會用繼承嗎?
阿新 • • 發佈:2018-06-03
類型 ostream ios rip code content pre 拷貝構造 NPU
Submit: 2599 Solved: 1892
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Problem B: 還會用繼承嗎?
Time Limit: 1 Sec Memory Limit: 128 MBSubmit: 2599 Solved: 1892
[Submit][Status][Web Board]
Description
定義一個Base類,包括1個int類型的屬性,以及滿足輸出格式要求的構造函數、拷貝構造函數和析構函數。
定義Base類的子類Derived,包括1個int類型的屬性, 以及滿足輸出格式要求的構造函數、拷貝構造函數和析構函數。
Input
第1行N>0表示測試用例個數。
每個測試包括2個int類型的整數。
Output
見樣例。
Sample Input
1 10 20
Sample Output
Base = 10 is created. Base = 10 is copied. Base = 10 is created. Derived = 20 is created. Base = 10 is copied. Derived = 20 is copied. Derived = 20 is erased. Base = 10 is erased. Derived = 20 is erased. Base = 10 is erased. Base = 10 is erased. Base = 10 is erased.
HINT
Append Code
append.cc,int main() { int cases, data1, data2; cin>>cases; for (int i = 0; i < cases; i++) { cin>>data1>>data2; Base base1(data1), base2(base1); Derived derived1(data1, data2), derived2(derived1); } }
#include <iostream> using namespace std; class Base { public : int num; Base(int t):num(t) { cout<<"Base = "<<num<<" is created."<<endl; } Base(const Base &p) { num=p.num; cout<<"Base = "<<num<<" is copied."<<endl; } ~Base() { cout<<"Base = "<<num<<" is erased."<<endl; } }; class Derived:public Base { public : int num2; Derived(int a, int b):Base(a), num2(b) { cout<<"Derived = "<<num2<<" is created."<<endl; } Derived(const Derived &p):Base(p),num2(p.num2)//子類可以拷貝給基類 { cout<<"Derived = "<<num2<<" is copied."<<endl; } ~Derived() { cout<<"Derived = "<<num2<<" is erased."<<endl; } }; int main() { int cases, data1, data2; cin>>cases; for (int i = 0; i < cases; i++) { cin>>data1>>data2; Base base1(data1), base2(base1); Derived derived1(data1, data2), derived2(derived1); } }
Problem B: 還會用繼承嗎?