Untitled

def dfs(x,y,ymax):
  ary[y][x]+=1
  if(y==ymax):
    return
  if(maps[y][x]=='S'):
    dfs(x-1,y+1,ymax)
    dfs(x+1,y+1,ymax)
  elif(maps[y][x]=='L'):
    dfs(x-1,y+1,ymax)
  elif(maps[y][x]=='R'):
    dfs(x+1,y+1,ymax)

ymax,xmax,enter=input().split()
ymax=int(ymax)
xmax=int(xmax)
enter=int(enter)
maps=[]
ary=[]

for j in range(ymax):
  tmp=input()
  maps.append(tmp)
  tmp=[]
  for i in range(xmax):
    tmp.append(int(0))
  ary.append(tmp)
  
tmp=[]
for i in range(xmax):
  tmp.append(int(0))
ary.append(tmp)

dfs(enter-1,0,ymax)
num=input().split()
ans=0
for i in range(xmax):
  ans+=int(num[i])*ary[ymax][i]
print(ans)