#include<iostream>
#include<string>
#include<math.h>
#include<algorithm>
#include<stdio.h>

using namespace std;

int main() {

	int h, w;
	cin >> h >> w;
	int** kami=new int*[h];
	for (int i = 0;i < h ;i++) {
		kami[i] = new int[w];
	}

	for (int i = 0;i < h;i++) {
		string str;
		cin >> str;
		for (int j = 0;j < w;j++) {
			if (str[j] == '0') {
				kami[i][j] = 0;
			}
			else if (str[j] == '1') kami[i][j] = 1;
		}
	}

	double sum = 0;
	double ans = 1000000;
	for (int i = 1;i <= h;i++) {
		for (int j = 0;j < h;j++) {
			for (int k = 0;k < w;k++) {
				if (kami[j][k] == 1) {
					sum += sqrt(pow(k + 1, 2) + pow(j + 1 - i, 2));
				}
			}
		}
		ans = min(ans,sum);
		sum = 0;
	}
	for (int i = 1;i <= h;i++) {
		for (int j = 0;j < h;j++) {
			for (int k = 0;k < w;k++) {
				if (kami[j][k] == 1) {
					sum += sqrt(pow(k + 1-(w+1), 2) + pow(j + 1 - i, 2));
				}
			}
		}
		ans = min(ans,sum);
		sum = 0;
	}
	for (int i = 1;i <= w;i++) {
		for (int j = 0;j < h;j++) {
			for (int k = 0;k < w;k ++ ) {
				if (kami[j][k] == 1) {
					sum += sqrt(pow(j+1,2)+pow(k+1-i,2));
				}
			}
		}
		ans = min(ans, sum);
		sum = 0;
	}
	
	for (int i = 1;i <= w;i++) {
		for (int j = 0;j < h;j++) {
			for (int k = 0;k < w;k++) {
				if (kami[j][k] == 1) {
					sum += sqrt(pow(j + 1 - (h+1), 2) + pow(k + 1 - i, 2));
				}
			}
		}
		ans = min(sum, ans);
		sum = 0;
	}
	
	printf("%.6f\n",ans);

	delete[] kami;

	return 0;
}