#include <iostream>
#include <string>
#include <map>
using namespace std;
int main(int argc, char* argv[]){
	 auto cmp = [](auto a, auto b){
	 	return a < b;
	 };
	 //与set类似，但是是以std::pair的形式返回的，记得写first,second 
	 map<int, string> a;
	 map<int, string, decltype(cmp)> b(cmp);
	 map<int, string> c;
	 b.insert({1,"111"});
	 b.insert({2,"222"});
	 b.insert({5,"555"});
	 b.insert(make_pair(3,"333"));
	 b.emplace(make_pair(4,"444"));
	 cout << b.count(3) << endl;
	//没有.at()和a[i]，树结构，不能直接访问第i个，可以it++ 
	 for(auto it = b.begin(); it != b.end(); it++){
	 	cout << it->first << ", " << it->second << " ";
	 }
	 cout << endl;
	 cout << b.find(3)->first << ", "<< b.find(3)->second << endl;
	 cout << b.upper_bound(4)->first << ", " << b.upper_bound(4)->second << endl;
	return 0;
}
/*
1
1, 111 2, 222 3, 333 4, 444 5, 555
3, 333
5, 555
*/