头文件：< algorithm >
1.两个数找最小值:

	int min_data = min(10,20);
    cout<< "min_data:" << min_data <<endl;  //10

2.找一个系列里的最小值 (使用initializer_list<>)

//利用min( {} )
	min_data = min({1,2,0,-40,-20,99});
    cout<< "min: "<< min_data <<endl;    //-40

3.查找容器里的最小值: min_element()

	array<int,10> myarr{10,-200,300,20,666};
    min_data = *min_element(myarr.begin(),myarr.end());    //返回迭代器
    cout<<"min: " << min_data <<"\n";

4.找最大值和最小值同理，将min改为max就可以.
5.在一个系列里同时查找最小值和最大值:minmax ，依然是使用 initializer_list<>技术

   pair<int,int> data = minmax({0,-20,20,1000,300});        //返回对组
   cout<<"min: " << data.first << "  max: " << data.second << "\n";

6.同时查找容器里的最小值和最大值 minmax_element

	array<int,10> myarr{10,-200,300,20,666};
   auto mydata = minmax_element(myarr.begin(),myarr.end());                 //返回对组,对组的每一个元素都是迭代器
   cout<<"min: " << *mydata.first << "  max: " << *mydata.second << "\n";