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Update 重要.cpp

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Implement some api which not implemented.
This commit is contained in:
kang sheng
2020-09-09 19:51:01 +08:00
committed by GitHub
parent 9b6ac0ef15
commit 1253b343a5
1 changed files with 78 additions and 57 deletions
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135
practical_exercises/10_day_practice/day7/综合例题/重要.cpp
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@@ -1,70 +1,91 @@
//<EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD>ַ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>String<EFBFBD><EFBFBD>ͨ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʵ<EFBFBD><EFBFBD><EFBFBD>ַ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>롢<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Լ<EFBFBD>+=<3D><>==<3D><>!=<3D><><<3C><>><3E><>>=<3D><>[ ]<5D><><EFBFBD><EFBFBD><EFBFBD>㡣
//设计一个字符串类String，通过运算符重载实现字符串的输入、输出以及+=、==、!=、<、>、>=、[ ]等运算。
#include <iostream>
#include <cstring>
using namespace std;
class String {
class String
{
private:
int length; //<2F>ַ<EFBFBD><D6B7><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
char *sPtr; //<2F><><EFBFBD><EFBFBD><EFBFBD>ַ<EFBFBD><D6B7><EFBFBD><EFBFBD><EFBFBD>ָ<EFBFBD><D6B8>
void setString( const char *s2);
friend ostream &operator<<(ostream &os, const String &s);
friend istream &operator>>(istream &is, String &s); //<2F><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
int length; //字符串长度
char *sPtr; //存放字符串的指针
void setString(const char *s2);
friend ostream &operator<<(ostream &os, const String &s)
{
return os << s.sPtr;
};
friend istream &operator>>(istream &is, String &s)
{
return is >> s.sPtr;
}; //重载输入运算符
public:
String( const char * = "" );
const String &operator=(const String &R); //<2F><><EFBFBD>ظ<EFBFBD>ֵ<EFBFBD><D6B5><EFBFBD><EFBFBD><EFBFBD><EFBFBD> =
const String &operator+=(const String &R); //<2F>ַ<EFBFBD><D6B7><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> +=
bool operator==(const String &R); //<2F>ַ<EFBFBD><D6B7><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ȱȽ<C8B1> ==
bool operator!=(const String &R); //<2F>ַ<EFBFBD><D6B7><EFBFBD><EFBFBD>IJ<EFBFBD><C4B2>ȱȽ<C8B1> !=
bool operator!() ; //<2F>ж<EFBFBD><D0B6>ַ<EFBFBD><D6B7><EFBFBD><EFBFBD>Ƿ<EFBFBD>Ϊ<EFBFBD><CEAA>
bool operator<(const String &R) const; //<2F>ַ<EFBFBD><D6B7><EFBFBD><EFBFBD><EFBFBD>С<EFBFBD>ڱȽ<DAB1> <
bool operator>(const String &R); //<2F>ַ<EFBFBD><D6B7><EFBFBD><EFBFBD>Ĵ<EFBFBD><C4B4>ڱȽ<DAB1> >
bool operator>=(const String &R); //<2F>ַ<EFBFBD><D6B7><EFBFBD><EFBFBD>Ĵ<EFBFBD><C4B4>ڵ<EFBFBD><DAB5>ڱȽ<DAB1>
char &operator[](int); //<2F>ַ<EFBFBD><D6B7><EFBFBD><EFBFBD><EFBFBD><EFBFBD>±<EFBFBD><C2B1><EFBFBD><EFBFBD><EFBFBD>
~String();
String(const char * = "");
const String &operator=(const String &R)
{
length = R.length;
strcpy(R.sPtr, sPtr);
return *this;
}; //重载赋值运算符 =
const String &operator+=(const String &R); //字符串的连接 +=
bool operator==(const String &R); //字符串的相等比较 ==
bool operator!=(const String &R); //字符串的不等比较 !=
bool operator!(); //判定字符串是否为空
bool operator<(const String &R) const; //字符串的小于比较 <
bool operator>(const String &R); //字符串的大于比较 >
bool operator>=(const String &R); //字符串的大于等于比较
char &operator[](int); //字符串的下标运算
~String(){};
};
const String &String::operator+=(const String &R) {
char *temp = sPtr;
length += R.length;
sPtr = new char[length+1];
strcpy(sPtr,temp );
strcat(sPtr,R.sPtr );
delete [] temp;
return *this;
const String &String::operator+=(const String &R)
{
char *temp = sPtr;
length += R.length;
sPtr = new char[length + 1];
strcpy(sPtr, temp);
strcat(sPtr, R.sPtr);
delete[] temp;
return *this;
}
bool String::operator==(const String &R){return strcmp(sPtr,R.sPtr)==0;}
bool String::operator!=(const String & R){return !(*this==R);}
bool String::operator!(){return length ==0;}
bool String::operator<(const String &R)const{return strcmp(sPtr,R.sPtr)<0;}
bool String::operator>(const String &R){return R<*this;}
bool String::operator>=(const String &R){return !(*this<R);}
char &String::operator[](int subscript){return sPtr[subscript];}
int main(){
String s1("happy"),s2("new year"),s3;
cout << "s1 is " << s1 << "\ns2 is " << s2 << "\ns3 is " << s3
<< "\n<EFBFBD>Ƚ<EFBFBD>s2<EFBFBD><EFBFBD>s1:"
<< "\ns2 ==s1<73><31><EFBFBD><EFBFBD><EFBFBD><EFBFBD> " << ( s2 == s1 ? "true" : "false")
<< "\ns2 != s1<73><31><EFBFBD><EFBFBD><EFBFBD><EFBFBD> " << ( s2 != s1 ? "true" : "false")
<< "\ns2 > s1<73><31><EFBFBD><EFBFBD><EFBFBD><EFBFBD> " << ( s2 > s1 ? "true" : "false")
<< "\ns2 < s1<73><31><EFBFBD><EFBFBD><EFBFBD><EFBFBD> " << ( s2 < s1 ? "true" : "false")
<< "\ns2 >= s1<73><31><EFBFBD><EFBFBD><EFBFBD><EFBFBD> " << ( s2 >= s1 ? "true" : "false");
cout << "\n\n<EFBFBD><EFBFBD><EFBFBD><EFBFBD>s3<EFBFBD>Ƿ<EFBFBD>Ϊ<EFBFBD><EFBFBD>: ";
if (!s3){
cout << "s3<EFBFBD>ǿմ<EFBFBD>"<<endl; //L3
cout<<"<EFBFBD><EFBFBD>s1<EFBFBD><EFBFBD><EFBFBD><EFBFBD>s3<EFBFBD>Ľ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ǣ<EFBFBD>";
s3 = s1;
cout << "s3=" << s3 << "\n"; //L5
String::String(const char *str)
{
sPtr = new char[strlen(str) + 1];
strcpy(sPtr, str);
length = strlen(str);
};
bool String::operator==(const String &R) { return strcmp(sPtr, R.sPtr) == 0; }
bool String::operator!=(const String &R) { return !(*this == R); }
bool String::operator!() { return length == 0; }
bool String::operator<(const String &R) const { return strcmp(sPtr, R.sPtr) < 0; }
bool String::operator>(const String &R) { return R < *this; }
bool String::operator>=(const String &R) { return !(*this < R); }
char &String::operator[](int subscript) { return sPtr[subscript]; }
int main()
{
String s1("happy"), s2("new year"), s3;
cout << "s1 is " << s1 << "\ns2 is " << s2 << "\ns3 is " << s3
<< "\n比较s2和s1:"
<< "\ns2 ==s1结果是 " << (s2 == s1 ? "true" : "false")
<< "\ns2 != s1结果是 " << (s2 != s1 ? "true" : "false")
<< "\ns2 > s1结果是 " << (s2 > s1 ? "true" : "false")
<< "\ns2 < s1结果是 " << (s2 < s1 ? "true" : "false")
<< "\ns2 >= s1结果是 " << (s2 >= s1 ? "true" : "false");
cout << "\n\n测试s3是否为空: ";
if (!s3)
{
cout << "s3是空串" << endl; //L3
cout << "把s1赋给s3的结果是：";
s3 = s1;
cout << "s3=" << s3 << "\n"; //L5
}
cout << "s1 += s2 <EFBFBD>Ľ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ǣ<EFBFBD>s1="; //L6
s1 += s2;
cout << s1; //L7
cout << "\ns1 += to you <EFBFBD>Ľ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ǣ<EFBFBD>"; //L8
s1 += " to you";
cout << "s1 = " << s1 <<endl; //L9
s1[0] = 'H';
cout << "s1 += s2 的结果是：s1="; //L6
s1 += s2;
cout << s1; //L7
cout << "\ns1 += to you 的结果是："; //L8
s1 += " to you";
cout << "s1 = " << s1 << endl; //L9
s1[0] = 'H';
s1[6] = 'N';
s1[10] = 'Y';
cout << "s1 = " << s1 << "\n"; //L10
cout << "s1 = " << s1 << "\n"; //L10
system("pause");
return 0;
}