#include <bits/stdc++.h>
using namespace std;

const int MX = 1000005;
int dat[MX], pre[MX], nxt[MX];
int unused = 1;

void insert(int addr, int num) {
	dat[unused] = num;
	
	pre[unused] = addr;
	nxt[unused] = nxt[addr];

	if (nxt[addr] != -1) pre[nxt[addr]] = unused;
	nxt[addr] = unused;
	
	unused++;
}

void erase(int addr) {
	nxt[pre[addr]] = nxt[addr];
	if (nxt[addr] != -1) pre[nxt[addr]] = pre[addr];
}

void traverse() {
	int cur = nxt[0];
	while (cur != -1) {
		cout << dat[cur] << ' ';
		cur = nxt[cur];
	}
	cout << "\n\n";
}

void insert_test() {
	cout << "****** insert_test *****\n";
	insert(0, 10); // 10(address=1)
	traverse();
	insert(0, 30); // 30(address=2) 10
	traverse();
	insert(2, 40); // 30 40(address=3) 10
	traverse();
	insert(1, 20); // 30 40 10 20(address=4)
	traverse();
	insert(4, 70); // 30 40 10 20 70(address=5)
	traverse();
}

void erase_test() {
	cout << "****** erase_test *****\n";
	erase(1); // 30 40 20 70
	traverse();
	erase(2); // 40 20 70
	traverse();
	erase(4); // 40 70
	traverse();
	erase(5); // 40
	traverse();
}

int main()
{
	ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);

	fill(pre, pre + MX, -1);
	fill(nxt, nxt + MX, -1);
	insert_test();
	erase_test();


	return 0;
}

#include <iostream>
#include <string>
#include <list>

using namespace std;

int main(void)
{
	ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);

	list<char>	editor;
	string		str;
	int			m;

	cin >> str;

	for (auto s : str)
	{
		editor.push_back(s);
	}

	cin >> m;

	auto cursor = editor.end();

	while (m--)
	{
		char command;

		cin >> command;

		switch (command)
		{
		case 'L':
			if (cursor != editor.begin())
			{
				cursor--;
			}
			break;
		case 'D':
			if (cursor != editor.end())
			{
				cursor++;
			}
			break;
		case 'B':
			if (cursor != editor.begin())
			{
				cursor = editor.erase(--cursor);
			}
			break;
		default:
			char s;
			cin >> s;
			editor.insert(cursor, s);
			break;
		}
	}

	for (auto s : editor)
	{
		cout << s;
	}

	return 0;
}

리스트(그외 반복자가 있는 컨테이너도 마찬가지일듯)의 erase 사용시 삭제된 원소 다음 반복자를 반환해주기 때문에 갱신을 시켜주어야 한다.

그렇지 않고 계속 사용하다간 Segmentation fault를 발생시킨다

#include <iostream>
#include <string>
#include <list>

using namespace std;

int main(void)
{
	ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);

	int	tc;

	cin >> tc;

	while (tc--)
	{
		list<char>	editor;
		auto		cursor = editor.begin();

		string		str;

		cin >> str;

		for (auto s : str)
		{
			switch (s)
			{
			case '<':
				if (cursor != editor.begin())
				{
					cursor--;
				}
				break;
			case '>':
				if (cursor != editor.end())
				{
					cursor++;
				}
				break;
			case '-':
				if (cursor != editor.begin())
				{
					cursor = editor.erase(--cursor);
				}
				break;
			default:
				editor.insert(cursor, s);
				break;
			}
		}

		for (auto s : editor)
		{
			cout << s;
		}
		cout << '\n';
	}

	return 0;
}

#include <iostream>
#include <string>
#include <list>

using namespace std;

int main(void)
{
	ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);

	list<int> josephus;

	int	n, k;
	int	idx = 1;

	cin >> n >> k;

	for (int i = 1; i <= n; ++i)
	{
		josephus.push_back(i);
	}

	auto iter = josephus.begin();

	cout << "<";

	while (true)
	{
		if (iter == josephus.end())
		{
			iter = josephus.begin();
		}

		if (idx % k == 0)
		{
			cout << *iter;
			iter = josephus.erase(iter); // 삭제된 원소 다음 반복자 반환

			if (josephus.empty())
			{
				break;
			}

			cout << ", ";
			idx++; // 삭제로 인해 자동으로 한칸이 밀렸으므로 인덱스도 맞춰줌

			continue;
		}
		
		iter++;
		idx++;
	}

	cout << ">";

	return 0;
}