#include <bits/stdc++.h>
using namespace std;

using pi = pair<int, int>;
const int N = 100100;
int w, h, sx, sy, ex, ey;
vector<int> a[N];

void foo(double x1, double y1, double x2, double y2) {

}

int main() {
    cin >> w >> h >> sx >> sy >> ex >> ey;
    if (sx > ex) swap(sx, ex), swap(sy, ey);
    for (int i = 0; i <= h / 2 + 1; i++)
        a[i].resize(w / 2 + 2);
    for (int i = 1; i <= h / 2; i++)
        for (int j = 1; j <= w / 2; j++)
            cin >> a[i][j];
    if (sy > ey) {
        sy = h - sy;
        ey = h - ey;
        reverse(a + 1, a + h / 2 + 1);
    }
    
    int ans = 0;

    double x = sx - ex, y = sy - ey, len = sqrt(x * x + y * y);
    
    if (sx == ex) {
        int last = -1;
        for (int y = sy; y <= ey; y += 2) {
            int i = sx / 2 + 1, j = y / 2 + 1;
            if (last != -1) ans += abs(last - a[j][i]);
            last = a[j][i];
        }
        cout << fixed << setprecision(12) << ans + len << "\n";
        return 0;
    }

    //cout << sx << " " << sy << " " << ex << " " << ey << "\n";

    vector<int> lower = {sy}, upper;
    for (int x = sx + 1; x < ex; x += 2) {
        long long A = 1ll * (ey - sy) * (x - sx), B = ex - sx;
        lower.push_back(sy + A / B - (A < 0 && A % B));
        upper.push_back(sy + A / B + (A > 0 && A % B));
    }
    upper.push_back(ey);


    for (int i = 0; i < lower.size(); i++) {
        lower[i] = lower[i] / 2 + 1;
        upper[i] = (upper[i] + 1) / 2 + 1;
        for (int j = lower[i]; j < upper[i] - 1; j++)
            ans += abs(a[j + 1][i + sx / 2 + 1] - a[j][i + sx / 2 + 1]);
    }

    for (int i = 1; i < lower.size(); i++) {
        if (lower[i] == upper[i - 1]) {
            int j = upper[i - 1];
            int A = a[j - 1][i - 1 + sx / 2 + 1];
            int B = a[j][i - 1 + sx / 2 + 1];
            int C = a[j - 1][i + sx / 2 + 1];
            int D = a[j][i + sx / 2 + 1];

            int val1 = B > A && B > D ? B * 2 - A - D : abs(A - D);
            int val2 = C > A && C > D ? C * 2 - A - D : abs(A - D);
            ans += min(val1, val2);
        } else {
            ans += abs(a[lower[i]][i + sx / 2 + 1] - a[lower[i]][i - 1 + sx / 2 + 1]);
        }
    }

    cout << fixed << setprecision(12) << ans + len << "\n";
    return 0;
}