h,w = map(int,raw_input().split())
a = [-1]*w+range(h)+range(h)+[h]*w
b = range(w)+[-1]*h+[w]*h+range(w)
mn = 1000000; d = list();
for y in xrange(h):
  s = raw_input()
  d += [[y,x] for x in range(w) if s[x] == '1']
for y1,x1 in zip(a,b):	
	mn = min(mn,sum(((y1-y2)**2+(x1-x2)**2)**.5 for y2,x2 in d))
print mn