[BOJ] 1874 스택 수열

 

https://www.acmicpc.net/problem/1874

1874번: 스택 수열

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;

namespace BOJ
{
    
    class Program
    {
        static void Main()
        {
            StreamReader sr = new StreamReader(Console.OpenStandardInput());
            StreamWriter sw = new StreamWriter(Console.OpenStandardOutput());
            StringBuilder sb = new StringBuilder();
            
            List<int> list = new List<int>();
            int number = 0;
            Stack<int> stack = new Stack<int>();

            int a = int.Parse(sr.ReadLine());
            for (int i = 0; i < a; i++)
            {
                list.Add(int.Parse(sr.ReadLine()));
            }
            for (int i = 1; i <= a; i++)
            {
                stack.Push(i);
                sb.Append("+" + "\n");

                while (stack.Count != 0 && stack.Peek() == list[number])
                {
                    stack.Pop();
                    sb.Append("-" + "\n");
                    number++;
                }
            }
            if (stack.Count == 0)
            {
                sw.WriteLine(sb);
            }
            else
            {
                sw.WriteLine("NO");
            }
            
            sr.Close();
            sw.Flush();
            sw.Close();
            

        }
    }
}