import numpy as np


height, width = [int(x) for x in input().split(' ')]
paint_place = []
length_lists = []

for y in range(1, height + 1):
    x_lists = [int(x) for x in input()]
    for x, i in enumerate(x_lists):
        if i == 1:
            paint_place.append([x + 1,y])
            
paint_place = np.array(paint_place)
if paint_place:
    for x in range(width + 2):
        for y in range(height + 2):
            if (((x == 0) or (x == width + 1)) and (1 <= y <= height)) or (((y == 0) or (y == height + 1)) and (1 <= x <= width)) :
                point = np. array([x, y])
                length_lists.append(np.sum(np.sqrt(np.sum(((paint_place - point) ** 2), axis=1))))
    print(min(length_lists))

else:
    print(0)