兰不达表达式
#include<iostream>
#include<vector>
#include<algorithm>//算法 lambda表达式，不仅仅适用与array ,也适用于vector
void main1()
{
std::vector<int> myvector;
myvector.push_back(11);
myvector.push_back(22);
myvector.push_back(33);
myvector.push_back(3);
myvector.push_back(4);
myvector.push_back(5);
int res=0;//结果
//&res直接操作一个变量，res等价于返回值，x代表参数，每次充当迭代器指向的元素，大括号就是代码
std::for_each(myvector.begin(), myvector.end(), [&res](int x){res += x; });
std::cout << res;
std::cin.get();
}
void main()
{
std::vector<int> myvector(5);//分配5个空间,默认初始化为0
myvector.push_back(1);//增
myvector.push_back(11);
myvector.push_back(111);
myvector.push_back(1111);
myvector.push_back(2);
myvector.pop_back();//弹出一个元素，删除最后一个
myvector.insert(myvector.begin() +1, 999);//插入，
myvector.erase(myvector.begin()+5);//根据迭代器的位置
//myvector.clear();//删除所有元素
for (int i = 0; i < myvector.size(); i++)
{
if (1)
{
//查询，修改
}
std::cout << myvector.at(i) << std::endl;
}
system("pause");
}
void main123123()
{
//可以实现动态无规则数组管理
std::vector<int> myvetor1;
myvetor1.push_back(12);
myvetor1.push_back(13);
myvetor1.push_back(14);
std::vector<int> myvetor2;
myvetor2.push_back(22);
std::vector<int> myvetor3;
myvetor3.push_back(32);
myvetor3.push_back(37);
std::vector<std::vector<int>> allvecor;
allvecor.push_back(myvetor1);
allvecor.push_back(myvetor2);
allvecor.push_back(myvetor3);
for (int i = 0; i < allvecor.size(); i++)
{
for (int j = 0; j < allvecor[i].size(); j++)
{
std::cout <<" "<< allvecor[i][j];
}
std::cout << "\n";
}
std::cin.get();
}
STL算法-操作数据
Vector
#include <iostream>
#include <vector>
#include <algorithm>
#include <list>
#include <set>
#include <string>
using namespace std;
void main1()
{
vector<int> myv;
myv.push_back(1);
myv.push_back(2);
myv.push_back(3);
myv.push_back(11);
myv.push_back(22);
myv.push_back(33);
for_each(myv.begin(), myv.end(), [](int v){ cout << v << endl; });
auto i = find(myv.begin(), myv.end(), 23);
if (i==myv.end())
{
std::cout << "23玩失踪";
}
else
{
std::cout <<*i;
}
cin.get();
}
void main2()
{
vector<int> myv;
myv.push_back(1);
myv.push_back(2);
myv.push_back(3);
myv.push_back(11);
myv.push_back(22);
myv.push_back(33);
for_each(myv.begin(), myv.end(), [](int v){ cout << v << endl; });
//auto i = find_if(myv.begin(), myv.end(), [](int v)->bool{ return (v > 4); });
auto i = find_if_not(myv.begin(), myv.end(), [](int v)->bool{ return (v > 4); });
if (i == myv.end())
{
std::cout << "玩失踪";
}
else
{
std::cout << *i;
}
cin.get();
}
List
template <class T>
class show
{
public:
void operator ()(T &t)
{
cout << t << " ";
}
};
void main3()
{
list <int > list1;
vector <int > v1;
list1.push_back(121);
list1.push_back(12);
list1.push_back(122);
list1.push_back(23);
v1.push_back(121);
v1.push_back(12);
v1.push_back(122);
v1.push_back(23);
//sort(list1.begin(), list1.end());//排序
//sort(v1.begin(), v1.end());//排序,简单的排序
//算法依赖于数据结构（链式，线性），不同的数据结构，算法不一样
fill(v1.begin() + 3, v1.end(), 3);//填充，指定位置数据进行初始化
for_each(list1.begin(), list1.end(), show<int>());
cout << "\n";
for_each(v1.begin(), v1.end(), show<int>());
cin.get();
}
Multiset
void main4()
{
multiset<int > myset;
myset.insert(3);
myset.insert(1);
myset.insert(2);
myset.insert(1);
myset.insert(2);
myset.insert(1);
myset.insert(2);
myset.insert(1);
int i = 0;
for (auto ib = myset.begin(), ie = myset.end(); ib != ie;ib++,i++)
{
}
cout << i << endl;
int num = count(myset.begin(), myset.end(), 1);//统计1有多少个节点
cout << num<< endl;
cin.get();
}
void main5()
{
multiset<int > myset;
myset.insert(3);
myset.insert(1);
myset.insert(2);
myset.insert(1);
myset.insert(0);
myset.insert(1);
myset.insert(2);
myset.insert(1);
for_each(myset.begin(),myset.end(), show< const int>());
auto it= adjacent_find(myset.begin(), myset.end());
cout << "\n" << *it << endl;
it++;
cout << "\n" << *it << endl;
it++;
cout << "\n" << *it << endl;
it++;
cout << "\n" << *it << endl;
it = adjacent_find(it, myset.end());//查找相同的数据，可以自己确定位置
cout << "\n" << *it << endl;
it++;
cout << "\n" << *it << endl;
cin.get();
}
打乱数据，扑克牌洗牌
template <class T>
class show
{
public:
void operator ()(T &t)
{
cout << t << " ";
}
};
//打乱数据
void main()
{
vector<int> v1;
for (int i = 0; i < 10;i++)
{
v1.push_back(i);
}
for_each(v1.begin(), v1.end(), show<int>());
cout << "\n";
random_shuffle(v1.begin(), v1.end());
for_each(v1.begin(), v1.end(), show<int>());
cout << "\n";
random_shuffle(v1.begin(), v1.end());
for_each(v1.begin(), v1.end(), show<int>());
cout << "\n";
random_shuffle(v1.begin(), v1.end());
for_each(v1.begin(), v1.end(), show<int>());
cin.get();
}
旋转数据
bool isok(int num)
{
return (num == 8);
}
//旋转数据
void main7()
{
vector<int> v1;
for (int i =10; i>0; i--)
{
v1.push_back(i);
}
for_each(v1.begin(), v1.end(), show<int>());
//partition(v1.begin(), v1.end(), isok);//服务于快速排序法的分区
//旋转， 头，尾，中间
rotate(v1.begin(), v1.begin()+8, v1.end());//v1.begin(), v1.begin()+8之间的数据移动到后面
cout << "\n";
for_each(v1.begin(), v1.end(), show<int>());
/*
rotate(v1.begin(), v1.begin()+1, v1.end());
cout << "\n";
for_each(v1.begin(), v1.end(), show<int>());
rotate(v1.begin(), v1.begin() + 1, v1.end());
cout << "\n";
for_each(v1.begin(), v1.end(), show<int>());
rotate(v1.begin(), v1.begin() + 1, v1.end());
cout << "\n";
for_each(v1.begin(), v1.end(), show<int>());
*/
cin.get();
}
排序并显示步骤
void main8()
{
int a[4] = { 2, 1, 3 ,10};
do
{
cout << a[0] << " " << a[1] << " " << a[2] <<a[3]<< "\n";
} while (prev_permutation(a,a+4));//排序并显示步骤
cin.get();
}
局部排序
void main10()
{
vector<char>one;
one.push_back('B');
one.push_back('A');
one.push_back('C');
one.push_back('Y');
one.push_back('Z');
one.push_back('X');
for_each(one.begin(), one.end(), show<char>());
cout << "\n";
for_each(one.begin(), one.end(), show<char>());
cin.get();
}
取出分数最低的2个学生
#include <iostream>
#include <vector>
#include <algorithm>
#include <list>
#include <set>
#include <string>
using namespace std;
class student
{
public:
string name;
int score;
public:
student(string str, int num) :name(str), score(num)
{
}
bool operator <(const student &s1)const
{
return this->score < s1.score;
}
};
//去分数最差的2个人
void main()
{
vector<student> ss;
{
student s1("银城A", 106);
ss.push_back(s1);
}
{
student s1("银城B", 101);
ss.push_back(s1);
}
{
student s1("银城C", 103);
ss.push_back(s1);
}
{
student s1("银城D", 105);
ss.push_back(s1);
}
partial_sort(ss.begin(), ss.begin() + 2,ss.end());//部分排序
for (int i = 0; i < 4;i++)
{
std::cout << ss[i].name << ss[i].score << "\n";
}
cin.get();
}
