#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 n, int i_start, int j_start, int i_end, int j_end) {
    //  Print the distance along with the sequence of moves.
    
    int dx[] = { -1, 1, 2, 1,-1, 2};
    int dy[] = { -2, -2,0, 2, 2,0};
    queue<cell> q;
    q.push(cell(i_start,j_start, 0));
    cell t;
    int x, y;
    bool visit[n+ 1][n + 1];
 
    //  make all cell unvisited
    for (int i = 1; i <= n; i++)
        for (int j = 1; j <= n; j++)
            visit[i][j] = false;
    
    visit[i_start][j_start] = true;
    
    while (!q.empty())
    {
        t = q.front();
        q.pop();
        visit[t.x][t.y] = true;
 
        // if current cell is equal to target cell,
        // return its distance
        if (t.x == i_end && t.y == j_end){
            cout<<t.dis;
            return;
        }
         else{
        //  loop for all reahable states
        for (int i = 0; i < 6; i++)
        {
            x = t.x + dx[i];
            y = t.y + dy[i];
 
            // If rechable state is not yet visited and
            // inside board, push that state into queue
            if (isInside(x, y, n) && !visit[x][y])
                q.push(cell(x, y, t.dis + 1));
 
        }
    }
    }
    cout<<"Impossible";
}





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(n, i_start, j_start, i_end, j_end);
    return 0;
}