class Wind:
    def __init__(self,x,y,dx,dy):
        self.x = x
        self.y = y
        self.dx = dx
        self.dy = dy
    def move(self):
        self.x=(self.x+self.dx)%asizex
        self.y=(self.y+self.dy)%asizey
    def __repr__(self):
        return f"{self.x},{self.y} {self.dx},{self.dy}"

decode={'v': (0,1), '^': (0,-1), '>': (1,0), '<': (-1,0)}
deltas=[0,-1,0,1,0]

infile=open("wind.txt")
lines=infile.read().split("\n")
asizex=len(lines[0])-2
asizey=len(lines)-2
start=(lines[0].find('.')-1,-1)
end=(lines[-1].find('.')-1, asizey)
winds=[Wind(x,y, *decode[ch])
       for y, line in enumerate(lines[1:-1]) for x,ch in enumerate(line[1:-1]) if ch != '.']
def nav(s,e):
    tokens={s}
    steps=0
    while e not in tokens:
        steps+=1
        nt=set()
        for token in tokens:
            nt.add(token)
            for i in range(4):
                nx=token[0]+deltas[i]
                ny=token[1]+deltas[i+1]
                if (0<=ny<asizey and 0<=nx<asizex) or (nx,ny)==e:
                    nt.add((nx,ny))
        for wi, wind in enumerate(winds):
            wind.move()
            nt.discard((wind.x,wind.y))
        tokens=nt
    return steps
print(nav(start,end)+nav(end,start)+nav(start,end))