Problem: Takahashi is locked within a building.

This building consists of H×W rooms, arranged in H rows and W columns. We will denote the room at the i-th row and j-th column as (i,j). The state of this room is represented by a character A_{i,j}. If A_{i,j}= `#`, the room is locked and cannot be entered; if A_{i,j}= `.`, the room is not locked and can be freely entered. Takahashi is currently at the room where A_{i,j}= `S`, which can also be freely entered.

Each room in the 1-st row, 1-st column, H-th row or W-th column, has an exit. Each of the other rooms (i,j) is connected to four rooms: (i-1,j), (i+1,j), (i,j-1) and (i,j+1).

Takahashi will use his magic to get out of the building. In one cast, he can do the following:

* Move to an adjacent room at most K times, possibly zero. Here, locked rooms cannot be entered.
* Then, select and unlock at most K locked rooms, possibly zero. Those rooms will remain unlocked from then on.



His objective is to reach a room with an exit. Find the minimum necessary number of casts to do so.

It is guaranteed that Takahashi is initially at a room without an exit.

Constraints

* 3 ≤ H ≤ 800
* 3 ≤ W ≤ 800
* 1 ≤ K ≤ H×W
* Each A_{i,j} is `#` , `.` or `S`.
* There uniquely exists (i,j) such that A_{i,j}= `S`, and it satisfies 2 ≤ i ≤ H-1 and 2 ≤ j ≤ W-1.

Input

Input is given from Standard Input in the following format:


H W K
A_{1,1}A_{1,2}...A_{1,W}
:
A_{H,1}A_{H,2}...A_{H,W}


Output

Print the minimum necessary number of casts.

Examples

Input

3 3 3
#.#
#S.
###


Output

1


Input

3 3 3
.#
S.


Output

1


Input

3 3 3

S#


Output

2


Input

7 7 2


...##
S###
.#.##
.###


Output

2

Solution (in PYTHON3):

Solution:
h,w,k=map(int, input().split())
s=[list(input()) for i in range(h)]
p=[[-1]*w for i in range(h)]
for i in range(h):
    for j in range(w):
        if s[i][j]=='S':
            sta=(i,j)
np=[(1,0),(-1,0),(0,1),(0,-1)]
q={sta}
p[sta[0]][sta[1]]=0
step=0
while step<k and q:
    step+=1
    nq=set()
    while q:
        now=q.pop()
        for i,j in np:
            nx,ny=now[0]+i,now[1]+j
            if nx<0 or nx==h or ny<0 or ny==w:continue
            if s[nx][ny]=='.' and p[nx][ny]==-1:
                p[nx][ny]=step
                nq.add((nx,ny))
    q=nq.copy()

ans=10**9
for i in range(h):
    for j in range(w):
        if p[i][j]>=0:
            an=min(i,j,h-i-1,w-j-1)
            if ans>an:ans=an
print(-(-ans//k)+1)