1.list-基本使用
#include <iostream>
#include <list>
using namespace std;
void main() {
list<int> lt;
//从头部添加
lt.push_front(10);
lt.push_front(20);
lt.push_front(30);
//从尾部添加
lt.push_back(40);
lt.push_back(50);
lt.push_back(60);
//循环遍历
for (list<int>::iterator it = lt.begin(); it != lt.end(); it++) {
cout << *it << endl;
}
list<int>::iterator it = lt.begin();
//连续相加允许(++)
//支持'++'、'--'运算符
it++;
it--;
cout << endl << "支持++、--运算符" << endl;
cout << *it << endl;
//注意:不支持间断
//不支持'+'、'-'运算度
// it = it - 1; 错误调用
getchar();
}
执行代码
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60
支持++、--运算符
30
2.list-删除
#include <iostream>
#include <list>
using namespace std;
void main() {
list<int> lt;
//从头部添加
lt.push_front(10);
lt.push_front(20);
lt.push_front(30);
//从尾部添加
lt.push_back(40);
lt.push_back(50);
lt.push_back(60);
cout << endl << "删除方式1:根据位置删除" << endl;
//删除方式1
list<int>::iterator it= lt.begin();
it++;
//删除:删除第二个元素
lt.erase(it);
//循环遍历
for (list<int>::iterator it = lt.begin(); it != lt.end(); it++) {
cout << *it << endl;
}
cout << endl << "删除方式2:直接根据内容删除" << endl;
//删除方式2
//直接根据内容删除
lt.remove(30);
//循环遍历
for (list<int>::iterator it = lt.begin(); it != lt.end(); it++) {
cout << *it << endl;
}
cout << endl << "删除方式3:区间删除" << endl;
//"删除方式3:区间删除
//开始位置
list<int>::iterator it_begin = lt.begin();
//结束位置
list<int>::iterator it_end = lt.begin();
it_end++;
it_end++;
//删除元素(如果已经被删除的元素不能够在删除)
lt.erase(it_begin, it_end);
//循环遍历
for (list<int>::iterator it = lt.begin(); it != lt.end(); it++) {
cout << *it << endl;
}
getchar();
}
执行代码
删除方式1:根据位置删除
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60
删除方式2:直接根据内容删除
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50
60
删除方式3:区间删除
50
60
3.list-插入
#include <iostream>
#include <list>
using namespace std;
void main() {
list<int> lt;
//从尾部添加
lt.push_back(40);
lt.push_back(50);
lt.push_back(60);
//插入
lt.insert(lt.begin(), 30);
//循环遍历
for (list<int>::iterator it = lt.begin(); it != lt.end(); it++) {
cout << *it << endl;
}
getchar();
}
执行代码
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40
50
60
4.set-基本使用(元素唯一,默认从小到大排列)
#include <iostream>
#include <set>
using namespace std;
void main() {
set<int> st;
st.insert(40);
st.insert(10);
st.insert(30);
st.insert(20);
//删除
set<int>::iterator it = st.begin();
st.erase(it);
for (set<int>::iterator it = st.begin(); it != st.end(); it++) {
cout << *it << endl;
}
getchar();
}
执行代码
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30
40
5set-从大到小排列
#include <iostream>
#include <set>
#include <functional>
using namespace std;
void main() {
set<int, greater<int> > st;
st.insert(40);
st.insert(10);
st.insert(30);
st.insert(20);
for (set<int>::iterator it = st.begin(); it != st.end(); it++) {
cout << *it << endl;
}
getchar();
}
执行代码
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30
20
10
6.set-基本使用(元素唯一,默认从小到大排列)
#include <iostream>
#include <set>
#include <functional>
using namespace std;
class Student {
private:
char* name;
int score;
public:
Student(char* name, int score) {
this->name = name;
this->score = score;
}
int getScore() {
return this->score;
}
void printStudent() {
cout << "name:" << this->name << " score:" << this->score << endl;
}
};
//仿函数
struct Soft {
//方式一:不写常量
// bool operator()(Student &left,Student &right){
// return left.getScore() < right.getScore();
// }
//方式二:const修饰
bool operator()(const Student &left, const Student &right) {
//类型转换
Student stu_left = const_cast<Student&>(left);
Student stu_right = const_cast<Student&>(right);
return stu_left.getScore() > stu_right.getScore();
}
};
void main() {
set<Student, Soft> st;
st.insert(Student("Jack", 96));
st.insert(Student("Pi", 63));
st.insert(Student("Song", 77));
st.insert(Student("Music", 88));
st.insert(Student("Lucy", 56));
for (set<Student>::iterator it = st.begin(); it != st.end(); it++) {
Student stu = const_cast<Student&>(*it);
stu.printStudent();
}
getchar();
}
执行代码
name:Jack score:96
name:Music score:88
name:Song score:77
name:Pi score:63
name:Lucy score:56
7.set-查找
对诸如set、map这种关键字唯一的集合而言,lower_bound、upper_bound返回迭代器是相同,关键字val在集合中不存在,二者返回结果一样,都是按照集合实例化时给定的Compare比较,不在val之前的第一个元素(亦即之后或者等于,如果按照默认的比较类型less,函数返回的是≥val的最小的元素);如果关键在val在集合中存在,lower_bound返回val关键字本身的迭代器,upper_bound返回关键字val下一个元素迭代器。
例1
#include <iostream>
#include <set>
#include <functional>
using namespace std;
typedef set<int> SET_INT;
int main()
{
SET_INT s1;
SET_INT::iterator i;
s1.insert(5);
s1.insert(10);
s1.insert(15);
s1.insert(20);
s1.insert(25);
cout << endl << "s1 -- starting at s1.lower_bound(12)" << endl;
// prints: 15,20,25
for (i = s1.lower_bound(12); i != s1.end(); i++)
cout << "s1 has " << *i << " in its set." << endl;
cout << endl << "s1 -- starting at s1.lower_bound(15)" << endl;
// prints: 15,20,25
for (i = s1.lower_bound(15); i != s1.end(); i++)
cout << "s1 has " << *i << " in its set." << endl;
cout << endl << "s1 -- starting at s1.upper_bound(12)" << endl;
// prints: 15,20,25
for (i = s1.upper_bound(12); i != s1.end(); i++)
cout << "s1 has " << *i << " in its set." << endl;
cout << endl << "s1 -- starting at s1.upper_bound(15)" << endl;
// prints: 20,25
for (i = s1.upper_bound(15); i != s1.end(); i++)
cout << "s1 has " << *i << " in its set." << endl;
cout << endl << "s1 -- starting s1.equal_range(12)" << endl;
// does not print anything
for (i = s1.equal_range(12).first; i != s1.equal_range(12).second; i++)
cout << "s1 has " << *i << " in its set." << endl;
cout << endl << "s1 -- starting s1.equal_range(15)" << endl;
// prints: 15
for (i = s1.equal_range(15).first; i != s1.equal_range(15).second; i++)
cout << "s1 has " << *i << " in its set." << endl;
getchar();
return 0;
}
执行代码
s1 -- starting at s1.lower_bound(12)
s1 has 15 in its set.
s1 has 20 in its set.
s1 has 25 in its set.
s1 -- starting at s1.lower_bound(15)
s1 has 15 in its set.
s1 has 20 in its set.
s1 has 25 in its set.
s1 -- starting at s1.upper_bound(12)
s1 has 15 in its set.
s1 has 20 in its set.
s1 has 25 in its set.
s1 -- starting at s1.upper_bound(15)
s1 has 20 in its set.
s1 has 25 in its set.
s1 -- starting s1.equal_range(12)
s1 -- starting s1.equal_range(15)
s1 has 15 in its set.
例2
#include <iostream>
#include <set>
#include <functional>
using namespace std;
/*Student结构体*/
struct Student {
string name;
int age;
string sex;
};
/*“仿函数"。为Student set指定排序准则*/
class studentSortCriterion {
public:
bool operator() (const Student &a, const Student &b) const {
/*先比较名字;若名字相同,则比较年龄。小的返回true*/
if (a.name < b.name)
return true;
else if (a.name == b.name) {
if (a.age < b.age)
return true;
else
return false;
}
else
return false;
}
};
int main()
{
set<Student, studentSortCriterion> stuSet;
Student stu1, stu2;
stu1.name = "Jack";
stu1.age = 13;
stu1.sex = "male";
stu2.name = "Marry";
stu2.age = 23;
stu2.sex = "female";
Student stu3;
stu3.name = "Lucy";
stu3.age = 23;
stu3.sex = "female";
stuSet.insert(stu1);
stuSet.insert(stu2);
stuSet.insert(stu3);
/*构造一个测试的Student,可以看到,即使stuTemp与stu1实际上并不是同一个对象,
*但当在set中查找时,仍会查找成功。这是因为已定义的studentSortCriterion的缘故。
*/
Student stuTemp;
stuTemp.name = "Marry";
stuTemp.age = 23;
set<Student, studentSortCriterion>::iterator iter;
iter = stuSet.find(stuTemp);
if (iter != stuSet.end()) {
cout << (*iter).name.c_str() << endl;
}
else {
cout << "Cannot fine the student!" << endl;
}
Student stuTemp2;
stuTemp.name = "Lili";
stuTemp.age = 13;
set<Student, studentSortCriterion>::iterator iter2;
iter2 = stuSet.find(stuTemp2);
if (iter2 != stuSet.end()) {
cout << (*iter).name.c_str() << endl;
}
else {
cout << "Cannot fine the student!" << endl;
}
getchar();
return 0;
}
执行代码
Marry
Cannot fine the student!
8.multiset-基本使用
- 允许存储重复元素
- 默认升序排列
#include <iostream>
#include <set>
#include <functional>
using namespace std;
class Student {
private:
char* name;
int score;
public:
Student(char* name, int score) {
this->name = name;
this->score = score;
}
int getScore() {
return this->score;
}
void printStudent() {
cout << "name:" << this->name << " score:" << this->score << endl;
}
};
//仿函数
struct Soft {
//方式一:不写常量
// bool operator()(Student &left,Student &right){
// return left.getScore() < right.getScore();
// }
//方式二:const修饰
bool operator()(const Student &left, const Student &right) {
//类型转换
Student stu_left = const_cast<Student&>(left);
Student stu_right = const_cast<Student&>(right);
return stu_left.getScore() > stu_right.getScore();
}
};
void main() {
cout << endl << "默认升序" << endl;
//升序
multiset<int> mst;
mst.insert(10);
mst.insert(20);
mst.insert(30);
mst.insert(10);
for (multiset<int>::iterator it = mst.begin(); it != mst.end(); it++) {
cout << *it << endl;
}
cout << endl << "使用greater降序" << endl;
//降序
multiset<int, greater<int> > mst2;
mst2.insert(10);
mst2.insert(20);
mst2.insert(30);
mst2.insert(10);
for (multiset<int>::iterator it = mst2.begin(); it != mst2.end(); it++) {
cout << *it << endl;
}
cout << endl << "自定义排序" << endl;
//自定义排序方式
multiset<Student, Soft> mst3;
mst3.insert(Student("Jack", 96));
mst3.insert(Student("Pi", 63));
mst3.insert(Student("Song", 77));
mst3.insert(Student("Music", 88));
mst3.insert(Student("Lucy", 56));
for (multiset<Student>::iterator it = mst3.begin(); it != mst3.end(); it++) {
Student stu = const_cast<Student&>(*it);
stu.printStudent();
}
getchar();
return;
}
执行代码
默认升序
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10
20
30
使用greater降序
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20
10
10
自定义排序
name:Jack score:96
name:Music score:88
name:Song score:77
name:Pi score:63
name:Lucy score:56
9.map-基本使用
#include <iostream>
#include <map>
#include <string>
#include <functional>
using namespace std;
void main() {
map<int, string> mp;
cout << endl << "方式1:插入数据pair" << endl;
//方式1:插入数据pair
mp.insert(pair<int, string>(01, "Lucy"));
mp.insert(pair<int, string>(02, "Cookie"));
mp.insert(pair<int, string>(03, "Sun"));
mp.insert(pair<int, string>(04, "Jack"));
for (map<int, string>::iterator it = mp.begin(); it != mp.end(); it++) {
//获取key:it->first
cout << "key:" << it->first << endl;
//获取value:it->second
cout << "value:" << it->second.c_str() << endl;
}
cout << endl << "方式2:pair" << endl;
//方式二:如果key存在,那么就不添加同时不覆盖,如果不存在,就添加
pair<map<int, string>::iterator, bool> result = mp.insert(map<int, string>::value_type(04, "Month"));
if (result.second) {
cout << "添加成功"<< endl;
}
else {
cout << "已存在,添加失败!" << endl;
}
for (map<int, string>::iterator it = mp.begin(); it != mp.end(); it++) {
//获取key:it->first
cout << "key:" << it->first << endl;
//获取value:it->second
cout << "value:" << it->second.c_str() << endl;
}
cout << endl << "方式3:make_pair" << endl;
//方式3:make_pair
mp.insert(make_pair(05, "Liu"));
for (map<int, string>::iterator it = mp.begin(); it != mp.end(); it++) {
//获取key:it->first
cout << "key:" << it->first << endl;
//获取value:it->second
cout << "value:" << it->second.c_str() << endl;
}
cout << endl << "方式4:" << endl;
//方式四:如果key存在,重复添加会覆盖,如果不存在,那就直接添加
mp[5] = "Ding";
mp[6] = "Coco";
for (map<int, string>::iterator it = mp.begin(); it != mp.end(); it++) {
//获取key:it->first
cout << "key:" << it->first<< endl;
//获取value:it->second
cout << "value:" << it->second.c_str() << endl;
}
getchar();
}
执行代码
方式1:插入数据pair
key:1
value:Lucy
key:2
value:Cookie
key:3
value:Sun
key:4
value:Jack
方式2:pair
已存在,添加失败!
key:1
value:Lucy
key:2
value:Cookie
key:3
value:Sun
key:4
value:Jack
方式3:make_pair
key:1
value:Lucy
key:2
value:Cookie
key:3
value:Sun
key:4
value:Jack
key:5
value:Liu
方式4:
key:1
value:Lucy
key:2
value:Cookie
key:3
value:Sun
key:4
value:Jack
key:5
value:Ding
key:6
value:Coco
10.map-删除
#include <iostream>
#include <map>
#include <string>
#include <functional>
using namespace std;
void main() {
map<int, string> mp;
//方式1:插入数据pair
mp.insert(pair<int, string>(01, "Lucy"));
mp.insert(pair<int, string>(02, "Cookie"));
mp.insert(pair<int, string>(03, "Sun"));
mp.insert(pair<int, string>(04, "Jack"));
//删除
map<int, string>::iterator it = mp.begin();
mp.erase(it);
for (map<int, string>::iterator it = mp.begin(); it != mp.end(); it++) {
//获取key:it->first
cout << "key:" << it->first << endl;
//获取value:it->second
cout << "value:" << it->second.c_str() << endl;
}
getchar();
}
执行代码
key:2
value:Cookie
key:3
value:Sun
key:4
value:Jack
11.map-查找(与set类似)
#include <iostream>
#include <map>
#include <string>
#include <functional>
using namespace std;
void main() {
map<int, string> mp;
mp.insert(pair<int, string>(01, "Lucy"));
mp.insert(pair<int, string>(02, "Cookie"));
mp.insert(pair<int, string>(03, "Sun"));
mp.insert(pair<int, string>(04, "Jack"));
map<int, string>::iterator it;
map<int, string>::iterator flag = mp.end();
it = mp.find(5);
if (it != flag)
{
(*it).second = "剩余";
}
else
{
cout << "没有找到" << endl;
}
// 该函数返回的是一对迭代器,第一个迭代器指向所查找元素的第一次出现的位置,
// 第二个迭代器指向所查找元素最后一次出现位置的后一个位置
pair<map<int, string>::iterator, map<int, string>::iterator> p = mp.equal_range(2);
if (p.first != mp.end())
{
cout << "key: " << p.first->first << endl;
cout << "value: " << p.first->second.c_str() << endl;
}
if (p.second != mp.end())
{
cout << "key: " << p.second->first << endl;
cout << "value: " << p.second->second.c_str() << endl;
}
getchar();
}
执行代码
没有找到
key: 2
value: Cookie
key: 3
value: Sun
12.multimap-一对多
使用场景:一个用户对应多个订单
#include <iostream>
#include <map>
#include <string>
#include <functional>
using namespace std;
class Order {
private:
char* name;
int num;
public:
Order(char* name, int num) {
this->name = name;
this->num = num;
}
void printOrder() {
cout << " 订单号:" << this->num << " 商品:"<< this->name << endl;
}
};
void main() {
multimap<string, Order> mst;
mst.insert(make_pair("Jack", Order("男士外套", 01)));
mst.insert(make_pair("Jack", Order("户外跑鞋", 02)));
mst.insert(make_pair("Lucy", Order("女士外套", 03)));
mst.insert(make_pair("Lucy", Order("女士高跟鞋",02)));
mst.insert(make_pair("Rose", Order("女士纱衣", 03)));
mst.insert(make_pair("Rose", Order("女士布鞋", 02)));
mst.insert(make_pair("Rose", Order("女士外套", 02)));
mst.insert(make_pair("Rose", Order("女士裤子", 02)));
//遍历
for (multimap<string,Order>::iterator it = mst.begin() ; it != mst.end() ; it++){
//获取key:it->first
cout << "key: " << it->first.c_str() << endl;
//获取value:it->second
Order order = const_cast<Order&>(it->second);
order.printOrder();
}
cout << endl << "只获取Lucy订单" << endl;
//获取订单的数量
int count = mst.count("Lucy");
//打印"梦想"订单:找到
multimap<string, Order>::iterator it = mst.find("Lucy");
//循环遍历打印
//计数
int i = 0;
while (it != mst.end() && i < count) {
cout << "key: " << it->first.c_str() << endl;
Order order = const_cast<Order&>(it->second);
order.printOrder();
i++;
it++;
}
getchar();
}
执行代码
key: Jack
订单号:1 商品:男士外套
key: Jack
订单号:2 商品:户外跑鞋
key: Lucy
订单号:3 商品:女士外套
key: Lucy
订单号:2 商品:女士高跟鞋
key: Rose
订单号:3 商品:女士纱衣
key: Rose
订单号:2 商品:女士布鞋
key: Rose
订单号:2 商品:女士外套
key: Rose
订单号:2 商品:女士裤子
只获取Lucy订单
key: Lucy
订单号:3 商品:女士外套
key: Lucy
订单号:2 商品:女士高跟鞋
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