black_point_list = []

h,w = [ int(v) for v in input().split() ]
for i in range(h):
	s = input()
	for j in range(w):
		if s[j] == "1":
			black_point_list.append((j+1,i+1))


def length(start,end):
    l = (((end[0]-start[0])**2.0 + (end[1]-start[1])**2.0))**0.5
    return l

up = [ (i+1,0) for i in range(w) ] 
down = [ (i+1,h+1) for i in range(w) ]
left = [ (0,i+1) for i in range(h) ]
right = [ (w+1,i+1) for i in range(h) ] 
surcum = up+down+left+right

anslist = []
for j in surcum:
	anslist.append(sum(list(map(length, [ j for i in range(len(black_point_list)) ] ,black_point_list))))

print(min(anslist))