#include <bits/stdc++.h>
using namespace std;
struct cell
{
    int x, y;
    int dis;
    cell() {}
    cell(int x, int y, int dis) : x(x), y(y), dis(dis) {}
};
 
bool isInside(int x, int y, int N)
{
    if (x >= 1 && x <= N && y >= 1 && y <= N)
        return true;
    return false;
}
 

void printShortestPath(int i_start,int i_end, int j_start,int j_end,int N)
{
    int dx[] = {-2, -2 , 0 , 2 , 2 , 0 };
    int dy[] = {-1,  1 , 2 , 1, -1 , -2};
 
    queue<cell> q;
 
    q.push(cell(i_start, i_end, 0));
 
    cell t;
    int x, y;
    bool visit[N + 1][N + 1];
 

    for (int i = 1; i <= N; i++)
        for (int j = 1; j <= N; j++)
            visit[i][j] = false;
 
 
    visit[i_start][i_end] = true;
 
    while (!q.empty())
    {
        t = q.front();
        q.pop();
        visit[t.x][t.y] = true;
        if (t.x == j_start && t.y == j_end)
        {
            cout<<t.dis<<endl;
            return ;
        }
 
        for (int i = 0; i < 6; i++)
        {
            x = t.x + dx[i];
            y = t.y + dy[i];
            if (isInside(x, y, N) && !visit[x][y])
                q.push(cell(x, y, t.dis + 1));
        }
    }
    cout<<"Impossible"<<endl;
}

int main() {
    int N;
    cin >> N;
    int i_start;
    int j_start;
    int i_end;
    int j_end;
    cin >> i_start >> j_start >> i_end >> j_end; 
    printShortestPath(i_start, i_end,j_start,j_end, N);
    return 0;
}