map

map 은 Key 값을 기준으로 중복 데이터가 불가

 

선언

map<string, int> map1;

 

 

데이터 추가

map1.insert({ "1st", 111 });
map1.insert({ "2nd", 222 });
map1.insert({ "3rd", 333 });
map1.insert({ "4th", 444 });
map1.insert({ "5th", 555 });

 

 

데이터 변경

map1["1st"] = 1;
map1["Last"] = 999;

 

 

데이터 찾기 및 삭제

iter = map1.find("4th");
if (iter == map1.end())
{
	printf("4th not found \n");
}
else
{
	cout << "4th found = "  << iter->first << " : " << iter->second << "\n";
}
map1.erase(iter);

 

 

키 기반 데이터 삭제

map1.erase("5th");

 

 

전체 데이터 삭제

map1.clear();

 

 

맵이 비어있는지 확인

map1.empty()

 

 

데이터 순환

for (iter = map1.begin(); iter != map1.end(); ++iter)
{
	cout << iter->first << " : " << iter->second << "\n";
}
printf("map1 size(%d) = %zd \n\n", map1.empty(), map1.size());

 

 

예제

#include <iostream>
#include <map>

using namespace std;

int main()
{
	map<string, int> map1;
	map<string, int>::iterator iter;

	printf("map1 size(%d) = %zd \n\n", map1.empty(), map1.size());

	map1.insert({ "1st", 111 });
	map1.insert({ "2nd", 222 });
	map1.insert({ "3rd", 333 });
	map1.insert({ "4th", 444 });
	map1.insert({ "5th", 555 });
	printf("map1 size(%d) = %zd \n\n", map1.empty(), map1.size());

	for (iter = map1.begin(); iter != map1.end(); ++iter)
	{
		cout << iter->first << " : " << iter->second << "\n";
	}
	printf("map1 size(%d) = %zd \n\n", map1.empty(), map1.size());

	iter = map1.find("4th");
	if (iter == map1.end())
	{
		printf("4th not found \n");
	}
	else
	{
		cout << "4th found = "  << iter->first << " : " << iter->second << "\n";
	}
	
	map1.erase(iter);

	iter = map1.find("4th");
	if (iter == map1.end())
	{
		printf("4th not found \n");
	}
	else
	{
		cout << "4th found = " << iter->first << " : " << iter->second << "\n";
	}

	map1.erase("5th");

	map1["1st"] = 1;
	map1["Last"] = 999;

	for (auto iter2 : map1)
	{
		cout << iter2.first << " : " << iter2.second << "\n";
	}
	printf("map1 size(%d) = %zd \n\n", map1.empty(), map1.size());

	map1.clear();
	printf("map1 size(%d) = %zd \n\n", map1.empty(), map1.size());

	int userInput;
	cin >> userInput;

	return 0;
}

 

 

STL

STL