Merge pull request #2 from frankie-yanfeng/patch-2

Update 程序填空.cpp

Author: chiuchiuuu

3.C++程序设计/week5/编程练习/程序填空.cpp

@@ -0,0 +1,117 @@
+#include <iostream>
+#include <cstdlib>
+#include <cstring>
+
+using namespace std;
+
+#include <string>
+#include <vector>
+#include <algorithm>
+#define qsort(a,b,c,d) myqsort(a,b,c,d)
+
+class MyString : public string
+{
+public:
+	MyString() {};
+	//1.0继承类继承父类所有的成员变量和成员函数，但不继承构造函数和析构函数
+	//1.1继承类的无参构造函数，会隐式调用父类的无参构造函数
+	MyString(const char * st) :string(st) {};
+	//1.2继承类的有参构造函数，如果父类也有有参构造函数，则必须显示调用它
+	//2.0这里的参数根据reference有两种选择，此处必须用const char*,"xxx"的类型是const char*
+	MyString(const MyString& s):string(s){}
+	//1.3继承类的复制构造函数必须要显示的调用父类的复制构造函数，不然就会默认调用父类的无参构造函数
+	MyString operator +(MyString & op2)
+	{
+		string s1 = *this;
+		string s2 = op2;
+		string s = s1 + s2;
+		return *new MyString(s.c_str());
+	}
+	MyString & operator +(const char * cs2)
+	{
+		string str1 = *this;
+		string s = str1 + cs2;
+		return *new MyString(s.c_str());
+	}
+
+	MyString & operator()(int s, int l)
+	{
+		string str = substr(s, l);
+		return *new MyString(str.c_str());
+	}
+};
+
+void print_test(MyString s)
+{
+	cout << s << endl;
+}
+
+int myqsort(MyString * ms,int size,int length,int (*f)(const void *,const void *))
+{
+	vector<MyString> vec;
+
+	for (int i=0; i< size; i++)
+		vec.push_back(ms[i]);
+
+	sort(vec.begin(), vec.end());
+
+	for (int i=0; i<size; i++)
+		//cout << vec[i] << endl;
+		ms[i]=vec[i];
+	return 0;
+
+}
+
+MyString operator+(const char * op1, MyString & op2)
+{
+	string st2 = op2;
+	string s = op1 + st2;
+	return *new MyString(s.c_str());
+}
+
+int CompareString(const void * e1, const void * e2)
+{
+	MyString * s1 = (MyString *)e1;
+	MyString * s2 = (MyString *)e2;
+	if (*s1 < *s2) return -1;
+	else if (*s1 == *s2) return 0;
+	else if (*s1 > *s2) return 1;
+}
+
+int main()
+{
+	MyString s1("abcd-"), s2, s3("efgh-");
+	MyString s4(s1);
+	MyString SArray[4] = { "big","me","about","take" };
+	//这里等号右边的赋值操作相当于调用了MyString的转换构造函数，其实就是单一非const classname&参数的构造函数可以直接接受参数类型的变量
+	cout << "1. " << s1 << s2 << s3 << s4 << endl;
+	s4 = s3;
+	//3.0 operator=可以直接用string类里面的
+	s3 = s1 + s3;
+	s1+s3;
+	cout << "2. " << s1 << endl;
+	cout << "3. " << s2 << endl;
+	cout << "4. " << s3 << endl;
+	cout << "5. " << s4 << endl;
+	cout << "6. " << s1[2] << endl;
+	s2 = s1;
+	s1 = "ijkl-";
+	s1[2] = 'A';
+	cout << "7. " << s2 << endl;
+	cout << "8. " << s1 << endl;
+	s1 += "mnop";
+	cout << "9. " << s1 << endl;
+	s4 = "qrst-" + s2;
+	cout << "10. " << s4 << endl;
+	s1 = s2 + s4 + " uvw " + "xyz";
+	cout << "11. " << s1 << endl;
+
+	qsort(SArray, 4, sizeof(MyString), CompareString);
+	//myqsort(SArray, 4, sizeof(MyString), CompareString);
+
+	for (int i = 0; i < 4; ++i)
+		cout << SArray[i] << endl;
+	cout << s1(0, 4) << endl;
+	cout << s1(5, 10) << endl;
+	return 0;
+}