BAEKJOON 1021 - 회전하는 큐

문제: https://www.acmicpc.net/problem/1021

front 와 back 의 삽입과 삭제가 자유로운 std::list 을 이용해 풀어봤습니다.

my solving

c++

#include <fstream>
#include <iostream>
#include <cstring>
#include <climits>
#include <algorithm>
 
#include <queue>
#include <list>
using namespace std;
 
list<int> numbers;
 
void pushLeft()
{
    int temp = numbers.front();
    numbers.pop_front();
    numbers.push_back(temp);
}
 
void pushRight()
{
    int temp = numbers.back();
    numbers.pop_back();
    numbers.push_front(temp);
}
 
bool isLeftbetterThenRight(int target)
{
    int count = 0;
    for (list<int>::iterator it = numbers.begin(); it != numbers.end(); it++)
    {
        count++;
        if (*it == target)
            break;    
    }
    if (count <= numbers.size() / 2 + 1)
        return true;
    else
        return false;
}
 
int main()
{
    int n, m;
    queue<int> needPopNumbers;
    
    cin >> n >> m;
    for (int i = 0; i < m; i++)
    {
        int num;
        cin >> num;
        needPopNumbers.push(num);
    }
 
    for (int i = 1; i <= n; i++)
        numbers.push_back(i);
 
    int ret = 0;
    while (needPopNumbers.empty() == false)
    {
        if (needPopNumbers.front() == numbers.front())
        {
            needPopNumbers.pop();
            numbers.pop_front();
        }
        else
        {
            if (isLeftbetterThenRight(needPopNumbers.front()))
                pushLeft();
            else
                pushRight();
            ret++;
        }
    }
    
    cout << ret << endl;
 
    return 0;
}