import math
H,W=map(int,input().split())
papers=[input() for _ in range(H)]
blacks = []

for x in range(H):
    for y in range(W):
        if papers[x][y] == '1':
            blacks.append([x+1,y+1])
result = pow(10,18)
for c in [0,W+1]:
    for a in range(1,H+1):
        tmp = 0
        for i in range(len(blacks)):
            tmp += math.sqrt(pow(blacks[i][0]-a,2)+pow(blacks[i][1]-c,2))
        result = min(result,tmp)
for r in [0,H+1]:
    for b in range(1,W+1):
        tmp = 0
        for i in range(len(blacks)):
            tmp += math.sqrt(pow(blacks[i][0]-r,2)+pow(blacks[i][1]-b,2))
        result = min(result,tmp)
print(result)