import math

h,w = map(int,input().split())
lst = []
min_value = float('inf')

for i in range(h):
    n = list(input())
    for j in range(w):
        if n[j]=="1":
            lst.append([i+1,j+1])

for i in [0,h+1]:
    for j in range(1,w+1):
        value = 0
        for tgt in lst:
            value += math.sqrt((tgt[0]-i)**2 + (tgt[1]-j)**2)
        min_value = min(min_value,value)

for i in [0,w+1]:
    for j in range(1,h+1):
        value = 0
        for tgt in lst:
            value += math.sqrt((tgt[0]-j)**2 + (tgt[1]-i)**2)
        min_value = min(min_value,value)

print(min_value)