from collections import deque
 
INF = float('inf')
MOD = 10 ** 9 + 7
dy = (0, 1)
dx = (1, 0)


H,W=map(int,input().split())
M = []
Max_list = []
for i  in range(H):
    t = input()
    M.append(t)
q = deque()
i,j = 0,0
dist = [[-1]*W for _ in range(H)]
if M[i][j] == '.':
    Ma = 0
    q.append((i, j,1))
    dist[i][j] = 0
    while q:
        cx,cy,c = q.popleft()
        for nx,ny in zip(dx,dy):
            x ,y= cx+nx,cy+ny
            if x<0 or y<0 or x>=H or y>=W:
                continue
            if M[x][y] == ".":
                if dist[x][y] == -1:
                    dist[x][y] =dist[cx][cy]+1
                    q.append((x,y,c))
                else:
                    if dist[cx][cy]+1<dist[x][y]:
                        dist[x][y] = dist[cx][cy]+1
                        q.append((x,y,c))
            if M[x][y] == "k":
                if dist[x][y] == -1:
                    dist[x][y] = (cx+cy)*2 + 1+c
                    q.append((x,y,c+1))
                else:
                    if (cx+cy)*2+1+c>dist[x][y]:
                        dist[x][y] =(cx+cy)*2+1+c
                        q.append((x,y,c+1))
# print(Max_list)
# print(dist)
print(dist[H-1][W-1])