#include "bits/stdc++.h"

#define REP(i, n, N) for(ll i=(n); i<(N); i++)
#define RREP(i, n, N) for(ll i=(N-1); i>=n; i--)
#define CK(n, a, b) ((a)<=(n)&&(n)<(b))
#define ALL(v) (v).begin(),(v).end()
#define p(s) cout<<(s)<<endl
#define p2(a, b) cout<<(a)<<" "<<(b)<<endl
#define v2(T) vector<vector<T>>
typedef long long int ll;
using namespace std;
const ll mod = 1e9 + 7;
const ll inf = 1e18;

ll H,W;
int main() {
    while(cin>>H>>W){
        string P[52];
        REP(i,1,H+1){
            cin>>P[i];
        }
        double ans=1e18;
        REP(i,0,H+2){
            REP(j,0,W+2){
                if((i==0||i==H+1||j==0||j==W+1)){
                    double tmp=0;
                    REP(y,1,H+1){
                        REP(x,0,W){
                            if(P[y][x]=='1'){
                                tmp+=sqrt((y-i)*(y-i)+(x+1-j)*(x+1-j));
                            }
                        }
                    }
                    ans=min(ans,tmp);
                }
            }
        }
        printf("%.7lf\n",ans);
    }
    return 0;
}