# Original solution

def getStart(field):
    search_field = field[1:]  
    for y in range(len(search_field)):
        for x in range(len(search_field[0])):
            if search_field[y][x] == "S":
                return x,y+1


def bfs(field,start_x,start_y,goal_N):
    direction = [[-1,0],[1,0],[0,-1],[0,1]]
    gotten_cheese = 1
    distance = 0
    que = []
    que.append([start_x,start_y,gotten_cheese,distance])
    INF = 1
    min_path = [[INF for j in range(field[0][1])] for i in range(field[0][0])]
    while len(que) != 0:
        current = que.pop(0)
        for d in direction:
            nx = current[0] + d[0]
            ny = current[1] + d[1]
            if 0 <= nx < field[0][1] and 1 <= ny < field[0][0]+1 and field[ny][nx] != "X" and min_path[ny-1][nx] == INF:
                if field[ny][nx] == current[2]: 
                    if field[ny][nx] == goal_N: 
                        print((current[3]+1))
                        return
                    else: # not goal, but could eat cheese
                        que = []
                        que.append([nx,ny,current[2]+1,current[3]+1])
                        min_path = [[INF for j in range(field[0][1])] for i in range(field[0][0])]
                        break
                else:
                    que.append([nx,ny,current[2],current[3]+1])
                    min_path[ny-1][nx] = 0


def main(field):

    sx,sy = getStart(field)
    bfs(field,sx,sy,field[0][2])

matrix = []
while True:
    row = input().rstrip().split()
    if len(row) == 3:
        re_row = []
        for i in row:
            re_row.append(int(i))
        matrix.append(re_row)
    else:
        re_row = []
        for char in row[0]:
            if char.isdigit():
                re_row.append(int(char))
            else:
                re_row.append(char)
        matrix.append(re_row)
    if len(matrix) == int(matrix[0][0]) + 1:
        main(matrix)
        break

# Optimized solution
import sys
sys.setrecursionlimit(100000000)
 
moves = [(0, -1), (0, 1), (-1, 0), (1, 0)]
 
 
def search(dataset):
    min_time = 0
    mouse = 1
    gx, gy = get_start(dataset)
    for i in range(N):
        gx, gy, min_time_tmp = bfs(dataset, (gx, gy), mouse)
        mouse += 1
        min_time += min_time_tmp
    print(min_time)
 
 
def bfs(dataset, start, mouse):
    INF = 10000000
    min_time = [[INF for j in range(W)] for i in range(H)]
    min_time[start[0]][start[1]] = 0
    queue = [start]
 
    while len(queue) != 0:
        dx, dy = queue.pop(0)
        for i, j in moves:
            nx = dx + i
            ny = dy + j
            if 0 <= nx < H and 0 <= ny < W and dataset[nx][ny] != 'X' and min_time[nx][ny] == INF:
                cell = dataset[nx][ny]
            else:
                continue
            if type(cell) is int:
                if mouse == int(cell):
                    min_time[nx][ny] = min_time[dx][dy] + 1
                    return nx, ny, min_time[nx][ny]
            min_time[nx][ny] = min_time[dx][dy] + 1
            queue.append((nx, ny))
 
 
def get_start(dataset):
    for i in range(H):
        rows = dataset[i]
        for j in range(W):
            cell = rows[j]
            if cell == 'S':
                return i, j
 
 
dataset = []
while True:
    line = input().rstrip().split()
    if len(line) == 3:
        H, W, N = list(map(int, line))
    else:
        row = []
        for e in line[0]:
            if e.isdigit():
                row.append(int(e))
            else:
                row.append(e)
        dataset.append(row)
    if len(dataset) == H:
        search(dataset)
        break