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문제

안대를 껴서 화면을 못 보는 채로 게임을 빨리 깨는 것을 "blindfolded speedrun"이라고 한다.

한 어드벤쳐 게임의 blindfolded speedrun 가이드북을 작성하던 중 난관에 봉착했다. 문제가 되는 파트의 난이도 자체가 높은 것은 아니다. 장애물이 격자 형태로 놓여 있고, 왼쪽 아래에서 출발해서 오른쪽 위로 가면 되는 간단한 파트다. 심지어 이 장애물도 게임을 킬 때마다 랜덤으로 배치되는 게 아니라 위치가 고정되어 있다. 문제는 처음에 어느 방향으로 서 있는지가 랜덤이라는 것이다. 안대를 꼈으니 방향을 알 방법이 없다.

N×N 격자가 있고, 2≤N≤20이다. 몇몇 칸에는 거대한 장애물이 있어서 지나갈 수 없고, 나머지는 비어 있어서 자유롭게 지나갈 수 있다. 격자 외부도 벽으로 둘러싸여 있어서 밖으로 나갈 수 없다. 주인공은 처음에 왼쪽 아래에 있고, 어느 방향으로 서 있는지는 모르지만 위와 오른쪽 중 하나인 것은 확실하다. 주인공은 매초 "전진", "좌회전", "우회전" 중 하나만 할 수 있다. 각 행동에는 1초가 걸린다. 전진하려고 하는데 앞에 장애물이나 벽이 있으면 그 자리에 그대로 있는다.

우리는 어느 방향으로 서 있는지에 관계 없이 오른쪽 위로 도착하도록 할 수 있는 가장 짧은 배열을 작성해야 한다. 도착하면 바로 컷신이 재생되므로 도착한 뒤 다른 칸으로 이탈할 일은 없다.

입력

첫 줄에는 N이 주어진다.

그 다음 N줄에는 격자의 행을 나타내는 길이 N의 스트링이 주어진다. E는 빈 칸이고, H는 장애물이다.

왼쪽 아래와 오른쪽 위는 무조건 E고, 왼쪽 아래에서 오른쪽 위로 가는 경로가 무조건 존재한다. (안 그러면 잘못 만든 게임이다.)

출력

가이드북에 쓸 수 있는 배열의 최소 길이를 출력한다.

예제 입력 1

3
EHE
EEE
EEE

예제 출력 1

9

힌트

"전진, 우회전, 전진, 전진, 좌회전, 전진, 좌회전, 전진, 전진"의 순서를 따르면 6초 또는 9초만에 도착할 수 있다.

[{"problem_id":"14451","problem_lang":"0","title":"\uc548\ub300 \ub080 \uc2a4\ud53c\ub4dc\ub7ec\ub108","description":"<p>\uc548\ub300\ub97c \uaef4\uc11c \ud654\uba74\uc744 \ubabb \ubcf4\ub294 \ucc44\ub85c \uac8c\uc784\uc744 \ube68\ub9ac \uae68\ub294 \uac83\uc744 &quot;blindfolded speedrun&quot;\uc774\ub77c\uace0 \ud55c\ub2e4.<\/p>\r\n\r\n<p>\ud55c \uc5b4\ub4dc\ubca4\uccd0 \uac8c\uc784\uc758 blindfolded speedrun \uac00\uc774\ub4dc\ubd81\uc744 \uc791\uc131\ud558\ub358 \uc911 \ub09c\uad00\uc5d0 \ubd09\ucc29\ud588\ub2e4. \ubb38\uc81c\uac00 \ub418\ub294 \ud30c\ud2b8\uc758 \ub09c\uc774\ub3c4 \uc790\uccb4\uac00 \ub192\uc740 \uac83\uc740 \uc544\ub2c8\ub2e4. \uc7a5\uc560\ubb3c\uc774 \uaca9\uc790 \ud615\ud0dc\ub85c \ub193\uc5ec \uc788\uace0, \uc67c\ucabd \uc544\ub798\uc5d0\uc11c \ucd9c\ubc1c\ud574\uc11c \uc624\ub978\ucabd \uc704\ub85c \uac00\uba74 \ub418\ub294 \uac04\ub2e8\ud55c \ud30c\ud2b8\ub2e4. \uc2ec\uc9c0\uc5b4 \uc774 \uc7a5\uc560\ubb3c\ub3c4 \uac8c\uc784\uc744 \ud0ac \ub54c\ub9c8\ub2e4 \ub79c\ub364\uc73c\ub85c \ubc30\uce58\ub418\ub294 \uac8c \uc544\ub2c8\ub77c \uc704\uce58\uac00 \uace0\uc815\ub418\uc5b4 \uc788\ub2e4. \ubb38\uc81c\ub294 \ucc98\uc74c\uc5d0 \uc5b4\ub290 \ubc29\ud5a5\uc73c\ub85c \uc11c \uc788\ub294\uc9c0\uac00 \ub79c\ub364\uc774\ub77c\ub294 \uac83\uc774\ub2e4. \uc548\ub300\ub97c \uaf08\uc73c\ub2c8 \ubc29\ud5a5\uc744 \uc54c \ubc29\ubc95\uc774 \uc5c6\ub2e4.<\/p>\r\n\r\n<p>N&times;N \uaca9\uc790\uac00 \uc788\uace0, 2&le;N&le;20\uc774\ub2e4. \uba87\uba87 \uce78\uc5d0\ub294 \uac70\ub300\ud55c \uc7a5\uc560\ubb3c\uc774 \uc788\uc5b4\uc11c \uc9c0\ub098\uac08 \uc218 \uc5c6\uace0, \ub098\uba38\uc9c0\ub294 \ube44\uc5b4 \uc788\uc5b4\uc11c \uc790\uc720\ub86d\uac8c \uc9c0\ub098\uac08 \uc218 \uc788\ub2e4. \uaca9\uc790 \uc678\ubd80\ub3c4 \ubcbd\uc73c\ub85c \ub458\ub7ec\uc2f8\uc5ec \uc788\uc5b4\uc11c \ubc16\uc73c\ub85c \ub098\uac08 \uc218 \uc5c6\ub2e4. \uc8fc\uc778\uacf5\uc740 \ucc98\uc74c\uc5d0 \uc67c\ucabd \uc544\ub798\uc5d0 \uc788\uace0, \uc5b4\ub290 \ubc29\ud5a5\uc73c\ub85c \uc11c \uc788\ub294\uc9c0\ub294 \ubaa8\ub974\uc9c0\ub9cc \uc704\uc640 \uc624\ub978\ucabd \uc911 \ud558\ub098\uc778 \uac83\uc740 \ud655\uc2e4\ud558\ub2e4. \uc8fc\uc778\uacf5\uc740 \ub9e4\ucd08 &quot;\uc804\uc9c4&quot;, &quot;\uc88c\ud68c\uc804&quot;, &quot;\uc6b0\ud68c\uc804&quot; \uc911 \ud558\ub098\ub9cc \ud560 \uc218 \uc788\ub2e4. \uac01 \ud589\ub3d9\uc5d0\ub294 1\ucd08\uac00 \uac78\ub9b0\ub2e4. \uc804\uc9c4\ud558\ub824\uace0 \ud558\ub294\ub370 \uc55e\uc5d0 \uc7a5\uc560\ubb3c\uc774\ub098 \ubcbd\uc774 \uc788\uc73c\uba74 \uadf8 \uc790\ub9ac\uc5d0 \uadf8\ub300\ub85c \uc788\ub294\ub2e4.<\/p>\r\n\r\n<p>\uc6b0\ub9ac\ub294 \uc5b4\ub290 \ubc29\ud5a5\uc73c\ub85c \uc11c \uc788\ub294\uc9c0\uc5d0 \uad00\uacc4 \uc5c6\uc774 \uc624\ub978\ucabd \uc704\ub85c \ub3c4\ucc29\ud558\ub3c4\ub85d \ud560 \uc218 \uc788\ub294 \uac00\uc7a5 \uc9e7\uc740 \ubc30\uc5f4\uc744 \uc791\uc131\ud574\uc57c \ud55c\ub2e4. \ub3c4\ucc29\ud558\uba74 \ubc14\ub85c \ucef7\uc2e0\uc774 \uc7ac\uc0dd\ub418\ubbc0\ub85c \ub3c4\ucc29\ud55c \ub4a4 \ub2e4\ub978 \uce78\uc73c\ub85c \uc774\ud0c8\ud560 \uc77c\uc740 \uc5c6\ub2e4.<\/p>\r\n","input":"<p>\uccab \uc904\uc5d0\ub294 N\uc774 \uc8fc\uc5b4\uc9c4\ub2e4.<\/p>\r\n\r\n<p>\uadf8 \ub2e4\uc74c N\uc904\uc5d0\ub294 \uaca9\uc790\uc758 \ud589\uc744 \ub098\ud0c0\ub0b4\ub294 \uae38\uc774 N\uc758 \uc2a4\ud2b8\ub9c1\uc774 \uc8fc\uc5b4\uc9c4\ub2e4. E\ub294 \ube48 \uce78\uc774\uace0, H\ub294 \uc7a5\uc560\ubb3c\uc774\ub2e4.<\/p>\r\n\r\n<p>\uc67c\ucabd \uc544\ub798\uc640 \uc624\ub978\ucabd \uc704\ub294 \ubb34\uc870\uac74 E\uace0, \uc67c\ucabd \uc544\ub798\uc5d0\uc11c \uc624\ub978\ucabd \uc704\ub85c \uac00\ub294 \uacbd\ub85c\uac00 \ubb34\uc870\uac74 \uc874\uc7ac\ud55c\ub2e4. (\uc548 \uadf8\ub7ec\uba74 \uc798\ubabb \ub9cc\ub4e0 \uac8c\uc784\uc774\ub2e4.)<\/p>\r\n","output":"<p>\uac00\uc774\ub4dc\ubd81\uc5d0 \uc4f8 \uc218 \uc788\ub294 \ubc30\uc5f4\uc758 \ucd5c\uc18c \uae38\uc774\ub97c \ucd9c\ub825\ud55c\ub2e4.<\/p>\r\n","hint":"<p>&quot;\uc804\uc9c4, \uc6b0\ud68c\uc804, \uc804\uc9c4, \uc804\uc9c4, \uc88c\ud68c\uc804, \uc804\uc9c4, \uc88c\ud68c\uc804, \uc804\uc9c4, \uc804\uc9c4&quot;\uc758 \uc21c\uc11c\ub97c \ub530\ub974\uba74 6\ucd08 \ub610\ub294 9\ucd08\ub9cc\uc5d0 \ub3c4\ucc29\ud560 \uc218 \uc788\ub2e4.<\/p>\r\n","original":"0","problem_lang_code":"\ud55c\uad6d\uc5b4"},{"problem_id":"14451","problem_lang":"1","title":"Cow Navigation","description":"<p>Bessie has gotten herself stuck on the wrong side of Farmer John&#39;s barn again, and since her vision is so poor, she needs your help navigating across the barn.<\/p>\r\n\r\n<p>The barn is described by an&nbsp;N&times;N grid of square cells (2&le;N&le;20), some being empty and some containing impassable haybales. Bessie starts in the lower-left corner (cell 1,1) and wants to move to the upper-right corner (cell&nbsp;N,N). You can guide her by telling her a sequence of instructions, each of which is either &quot;forward&quot;, &quot;turn left 90 degrees&quot;, or &quot;turn right 90 degrees&quot;. You want to issue the shortest sequence of instructions that will guide her to her destination. If you instruct Bessie to move off the grid (i.e., into the barn wall) or into a haybale, she will not move and will skip to the next command in your sequence.<\/p>\r\n\r\n<p>Unfortunately, Bessie doesn&#39;t know if she starts out facing up (towards cell 1,2) or right (towards cell 2,1). You need to give the shortest sequence of directions that will guide her to the goal regardless of which case is true. Once she reaches the goal she will ignore further commands.<\/p>\r\n","input":"<p>The first line of input contains&nbsp;N.<\/p>\r\n\r\n<p>Each of the&nbsp;N&nbsp;following lines contains a string of exactly&nbsp;N&nbsp;characters, representing the barn. The first character of the last line is cell 1,1. The last character of the first line is cell N, N.<\/p>\r\n\r\n<p>Each character will either be an H to represent a haybale or an E to represent an empty square.<\/p>\r\n\r\n<p>It is guaranteed that cells 1,1 and&nbsp;N,N will be empty, and furthermore it is guaranteed that there is a path of empty squares from cell 1,1 to cell&nbsp;N,N.<\/p>\r\n","output":"<p>On a single line of output, output the length of the shortest sequence of directions that will guide Bessie to the goal, irrespective whether she starts facing up or right.<\/p>\r\n\r\n<p>&nbsp;<\/p>\r\n","hint":"<p>In this example, the instructions &quot;Forward, Right, Forward, Forward, Left, Forward, Left, Forward, Forward&quot; will guide Bessie to the destination irrespective of her starting orientation.<\/p>\r\n\r\n<p>&nbsp;<\/p>\r\n","original":"1","problem_lang_code":"\uc601\uc5b4"}]