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C++第八天
今天讲的主要是list和map容器。将涉及到的函数也都讲到了,都有案例。今天讲的内容已经尽量添加备注了,方便以后查看。明天最后一天C++了,今天老师就将项目资料给我们要求我们做准备了,看了一眼,感觉难度不小,比第一个项目难度要大一些。
map查找速度快,会自动排序
map:也是类模板,里面放一对数据,第一个是键,第二个是值,内部实现是通过二叉树实现的
红黑树是一种特殊的二叉树,插入的时候会自动排序
树的遍历有前序遍历(顺序是中左右)、后序遍历(顺序是左右中)、中序遍历(顺序是左中右,结果是从小到大),前、后、中指的是根节点的位置
#include <iostream>
#include <string>
#include <map>
using namespace std;
//map:存放键值对数据,键唯一,不能重复
//若已存在键,则插入数据失败
typedef map<int, string> PEOMAP;
void print(const PEOMAP &peo)
{
PEOMAP::const_iterator iter;
iter = peo.begin();
for (; iter != peo.end(); iter++)
{
cout << iter->first << ' ' << iter->second<< '\n';
}
}
int main(void)
{
map<int, string> people;
people.insert(pair<int,string>(1001, "zhangsan"));//pair是用来保留一对数据的类模板
people.insert(pair<int,string>(1009, "lisi"));
people.insert(pair<int,string>(1006, "wangwu"));
people.insert(pair<int,string>(1003, "zhaoliu"));
people.insert(pair<int,string>(1007, "xiaoqi"));
print(people);
#if 0 //上面写法相当于:
pair<int,string> p(1001,"zhangsan");
people.insert(p);
#endif
return 0;
}
#include <iostream>
#include <string>
#include <map>
using namespace std;
//map:存放键值对数据,键唯一,不能重复
//若已存在键,则插入数据失败
typedef map<int, string> PEOMAP;
void print(const PEOMAP &peo)
{
PEOMAP::const_iterator iter;
iter = peo.begin();
for (; iter != peo.end(); iter++)
{
cout << iter->first << ' ' << iter->second<< '\n';
}
}
int main(void)
{
map<int, string> people;
people.insert(pair<int,string>(1001, "zhangsan"));
//下标使用方法
//string str = people[1009];//没有的会自动创建
people[1001] = "hhashsha";//有的话会覆盖原值
people[1009] = "$$$$$";//没有的话会创建
//cout << people.at(1010) << endl;
print(people);
return 0;
}
#include <iostream>
#include <list>
using namespace std;
template<typename U>
void print(const list<U> &mylist)
{
typename list<U>::const_iterator iter;
iter = mylist.begin();
for (; iter != mylist.end(); iter++)
{
cout << *iter << endl;
}
}
bool predicate(int &a)
{
if (0 == a%2)
{
return true;
}
return false;
}
bool mycompare(int &a, int &b)
{
return a > b;
}
int main(void)
{
list<int> mylist;
mylist.push_back(15);
mylist.push_back(17);
mylist.push_back(25);
mylist.push_back(77);
mylist.push_front(16);
mylist.push_front(86);
mylist.push_front(26);
// mylist.push_front(16);
// mylist.push_front(16);
print(mylist);
// mylist.remove(17);//移除指定的内容
// mylist.remove_if(predicate);//删除满足条件的内容
// mylist.unique();//删除连续的内容,保留唯一的内容
// mylist.sort();//默认从小到大排序
mylist.sort(mycompare);//定义条件从大到小排序
cout << "-----------------\n";
print(mylist);
return 0;
}
#include <iostream>
#include <list>
using namespace std;
template<typename U>
void print(const list<U> &mylist)
{
typename list<U>::const_iterator iter;//迭代器也是一个类模板
iter = mylist.begin();
for (; iter != mylist.end(); iter++)
{
cout << *iter << ' ';
}
cout << '\n';
}
int main(void)
{
int arr1[7] = {18, 67, 34, 6, 15, 2, 9};
list<int> l1(arr1, arr1+7);
l1.sort();
print(l1);
int arr2[5] = {33, 67, 22, 17, 32};
list<int> l2(arr2, arr2+5);
l2.sort();
print(l2);
l1.merge(l2);//合并
cout << "l1:";
print(l1);
cout << "l2:";
print(l2);
return 0;
}
#include <iostream>
#include <vector>
#include <string>
#include <string.h>
using namespace std;
class Student
{
public:
Student(){}
Student(const char *name, float score=0)
{
strcpy(m_caName, name);
m_fScore = score;
}
float getScore()
{
return m_fScore;
}
friend ostream &operator<<(ostream &out, const Student *stu);
friend ostream &operator<<(ostream &out, const Student &stu);
private:
char m_caName[32];
float m_fScore;
};
ostream &operator<<(ostream &out, const Student *stu)
{
out << stu->m_caName << ' ' << stu->m_fScore;
return out;
}
ostream &operator<<(ostream &out, const Student &stu)
{
out << stu.m_caName << ' ' << stu.m_fScore;
return out;
}
template<typename U>
void print(const list<U> &mylist)
{
typename list<U>::const_iterator iter;
iter = mylist.begin();
for (; iter != mylist.end(); iter++)
{
cout << *iter << endl;
}
}
bool compare(Student* &s1, Student* &s2)
{
return s1->getScore() > s2->getScore();
}
int main(void)
{
list<Student *> stulist;
stulist.push_back(new Student("aa", 89));
stulist.push_back(new Student("bb", 79));
stulist.push_back(new Student("cc", 99));
stulist.push_back(new Student("dd", 69));
stulist.push_back(new Student("ee", 88));
print(stulist);
cout << "-------------------\n";
stulist.sort(compare);//排序
print(stulist);
return 0;
}
#include <iostream>
#include <vector>
#include <string>
#include <string.h>
using namespace std;
class Student
{
public:
Student(){}
Student(const char *name, float score=0)
{
strcpy(m_caName, name);
m_fScore = score;
}
float getScore()
{
return m_fScore;
}
friend ostream &operator<<(ostream &out, const Student *stu);
friend ostream &operator<<(ostream &out, const Student &stu);
private:
char m_caName[32];
float m_fScore;
};
ostream &operator<<(ostream &out, const Student *stu)
{
out << stu->m_caName << ' ' << stu->m_fScore;
return out;
}
ostream &operator<<(ostream &out, const Student &stu)
{
out << stu.m_caName << ' ' << stu.m_fScore;
return out;
}
template<typename U>
void print(const list<U> &mylist)
{
typename list<U>::const_iterator iter;
iter = mylist.begin();
for (; iter != mylist.end(); iter++)
{
cout << *iter << endl;
}
}
bool compare(Student &s1, Student &s2)
{
return s1.getScore() > s2.getScore();
}
int main(void)
{
list<Student> stulist;
stulist.push_back(Student("aa", 89));
stulist.push_back(Student("bb", 79));
stulist.push_back(Student("cc", 99));
stulist.push_back(Student("dd", 69));
stulist.push_back(Student("ee", 88));
print(stulist);
cout << "-------------------\n";
stulist.sort(compare);//排序
print(stulist);
return 0;
}
#include <iostream>
#include <vector>
#include <string>
#include <string.h>
using namespace std;
class Student
{
public:
Student(){}
Student(const char *name, float score=0)
{
strcpy(m_caName, name);
m_fScore = score;
}
bool operator <(const Student &other)
{
return m_fScore < other.m_fScore;
}
friend ostream &operator<<(ostream &out, const Student *stu);
friend ostream &operator<<(ostream &out, const Student &stu);
private:
char m_caName[32];
float m_fScore;
};
ostream &operator<<(ostream &out, const Student *stu)
{
out << stu->m_caName << ' ' << stu->m_fScore;
return out;
}
ostream &operator<<(ostream &out, const Student &stu)
{
out << stu.m_caName << ' ' << stu.m_fScore;
return out;
}
template<typename U>
void print(const list<U> &mylist)
{
typename list<U>::const_iterator iter;
iter = mylist.begin();
for (; iter != mylist.end(); iter++)
{
cout << *iter << endl;
}
}
int main(void)
{
list<Student> stulist;
stulist.push_back(Student("aa", 89));
stulist.push_back(Student("bb", 79));
stulist.push_back(Student("cc", 99));
stulist.push_back(Student("dd", 69));
stulist.push_back(Student("ee", 88));
print(stulist);
cout << "-------------------\n";
stulist.sort();
print(stulist);
return 0;
}
#include <iostream>
#include <vector>
#include <string>
#include <string.h>
using namespace std;
//map:存放键值对数据,键唯一,不能重复
//若已存在键,则插入数据失败
class Student
{
public:
Student(){}
Student(const char *name, float score=0)
{
strcpy(m_caName, name);
m_fScore = score;
}
bool operator<(const Student &other) const
{
return m_fScore <other.m_fScore;
}
float getScore()
{
return m_fScore;
}
friend ostream &operator<<(ostream &out, const Student *stu);
friend ostream &operator<<(ostream &out, const Student &stu);
private:
char m_caName[32];
float m_fScore;
};
ostream &operator<<(ostream &out, const Student *stu)
{
out << stu->m_caName << ' ' << stu->m_fScore;
return out;
}
ostream &operator<<(ostream &out, const Student &stu)
{
out << stu.m_caName << ' ' << stu.m_fScore;
return out;
}
typedef map<int, Student*> PEOMAP;
typedef pair<int, Student*> PAIR;
void print(const PEOMAP &peo)
{
PEOMAP::const_iterator iter;
iter = peo.begin();
for (; iter != peo.end(); iter++)
{
cout << iter->first << ' ' << iter->second<< '\n';
}
}
int main(void)
{
map<int, Student*> people;
people.insert(PAIR(1001, new Student("zhangsan", 90)));
people.insert(PAIR(1009, new Student("lisi", 89)));
people.insert(PAIR(1006, new Student("wangwu", 99)));
people.insert(PAIR(1003, new Student("zhaoliu", 78)));
people.insert(PAIR(1007, new Student("xiaoqi", 62)));
print(people);
#if 0
pair<int,string> p(1001,"zhangsan");
people.insert(p);
#endif
return 0;
}
#include <iostream>
#include <string>
#include <map>
#include <list>
#include "student.h"
using namespace std;
class Student
{
public:
Student(){}
Student(const char *name, float score=0)
{
strcpy(m_caName, name);
m_fScore = score;
}
bool operator<(const Student &other) const
{
return m_fScore <other.m_fScore;
}
float getScore()
{
return m_fScore;
}
friend ostream &operator<<(ostream &out, const Student *stu);
friend ostream &operator<<(ostream &out, const Student &stu);
private:
char m_caName[32];
float m_fScore;
};
ostream &operator<<(ostream &out, const Student *stu)
{
out << stu->m_caName << ' ' << stu->m_fScore;
return out;
}
ostream &operator<<(ostream &out, const Student &stu)
{
out << stu.m_caName << ' ' << stu.m_fScore;
return out;
}
typedef map<int, Student*> PEOMAP;
typedef pair<int, Student*> PAIR;
bool compare(PAIR &p1, PAIR &p2)
{
return p1.second->getScore() > p2.second->getScore();
}
void print(const PEOMAP &peo)
{
PEOMAP::const_iterator iter;
iter = peo.begin();
for (; iter != peo.end(); iter++)
{
cout << iter->first << ' ' << iter->second<< '\n';
}
}
int main(void)
{
map<int, Student*> people;
people.insert(PAIR(1001, new Student("zhangsan", 90)));
people.insert(PAIR(1009, new Student("lisi", 89)));
people.insert(PAIR(1006, new Student("wangwu", 99)));
people.insert(PAIR(1003, new Student("zhaoliu", 78)));
people.insert(PAIR(1007, new Student("xiaoqi", 62)));
print(people);
cout << "---------------\n";
list<PAIR> test;
PEOMAP::iterator iter;
iter = people.begin();
for (; iter != people.end(); iter++)
{
test.push_back(*iter);
}
test.sort(compare);
list<PAIR>::iterator iter2;
iter2 = test.begin();
for (; iter2 != test.end(); iter2++)
{
cout << iter2->first<< ' ' << iter2->second<< '\n';
}
return 0;
}
#include <iostream>
#include <vector>
#include <string>
#include <string.h>"
using namespace std;
class Student
{
public:
Student(){}
Student(const char *name, float score=0)
{
strcpy(m_caName, name);
m_fScore = score;
}
bool operator<(const Student &other) const
{
return m_fScore <other.m_fScore;
}
float getScore()
{
return m_fScore;
}
friend ostream &operator<<(ostream &out
, const Student *stu);
friend ostream &operator<<(ostream &out
, const Student &stu);
private:
char m_caName[32];
float m_fScore;
};
ostream &operator<<(ostream &out
, const Student *stu)
{
out << stu->m_caName
<< ' ' << stu->m_fScore;
return out;
}
ostream &operator<<(ostream &out
, const Student &stu)
{
out << stu.m_caName
<< ' ' << stu.m_fScore;
return out;
}
typedef map<Student, int> PEOMAP;
typedef pair<Student, int> PAIR;
void print(const PEOMAP &peo)
{
PEOMAP::const_iterator iter;
iter = peo.begin();
for (; iter != peo.end(); iter++)
{
cout << iter->first
<< ' ' << iter->second
<< '\n';
}
}
int main(void)
{
map<Student, int> people;
people.insert(PAIR(Student("zha", 90), 1001));
people.insert(PAIR(Student("as", 80), 1009));
people.insert(PAIR(Student("bs", 79), 1005));
people.insert(PAIR(Student("usb", 99), 1008));
people.insert(PAIR(Student("sca", 77), 1002));
print(people);
return 0;
}
#include <iostream>
#include <map>
#include <list>
#include <vector>
#include <string>
#include <string.h>
using namespace std;
class Student
{
public:
Student(){}
Student(const char *name, float score=0)
{
strcpy(m_caName, name);
m_fScore = score;
}
bool operator<(const Student &other) const
{
return m_fScore <other.m_fScore;
}
float getScore()
{
return m_fScore;
}
friend ostream &operator<<(ostream &out, const Student *stu);
friend ostream &operator<<(ostream &out, const Student &stu);
private:
char m_caName[32];
float m_fScore;
};
ostream &operator<<(ostream &out, const Student *stu)
{
out << stu->m_caName << ' ' << stu->m_fScore;
return out;
}
ostream &operator<<(ostream &out, const Student &stu)
{
out << stu.m_caName << ' ' << stu.m_fScore;
return out;
}
class Compare
{
public:
bool operator()(Student *s1, Student *s2)
{
return s1->getScore()>s2->getScore();
}
};
typedef map<Student*, int, Compare> PEOMAP;
typedef pair<Student*, int> PAIR;
void print(const PEOMAP &peo)
{
PEOMAP::const_iterator iter;
iter = peo.begin();
for (; iter != peo.end(); iter++)
{
cout << iter->first << ' ' << iter->second<< '\n';
}
}
int main(void)
{
PEOMAP people;
people.insert(PAIR(new Student("zha", 90), 1001));
people.insert(PAIR(new Student("as", 80), 1009));
people.insert(PAIR(new Student("bs", 79), 1005));
people.insert(PAIR(new Student("usb", 99), 1008));
people.insert(PAIR(new Student("sca", 77), 1002));
print(people);
return 0;
}
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