#codingexercise
Generate a 2D distance matrix for the nearest distance from each cell as city location to  a parking spot that appears as one or more occupied cells.

 static int[][] getParkingDistanceGrid(int cityLength, int cityWidth, int[] parkingXCoordinates, int[] parkingYCoordinates) {

        var d = new int[cityWidth][];

        for (int i = 0; i < cityWidth; i++)

            d[i] = new int[cityLength];

        for (int i = 0; i < cityWidth; i++)

        {

            for (int j = 0; j < cityLength; j++)

                {

                    var parkingdistances = new List<int>();

                    for (int count = 0; count < parkingXCoordinates.Length; count++)

                    {

                        int distance = GetDistance(i+1, j+1, parkingXCoordinates[count], parkingYCoordinates[count]);

                        parkingdistances.Add(distance);

                    }

                    int min = INT_MAX;

                    for (int k = 0; k < parkingXCoordinates.Length; k++)

                        if (parkingdistances[k] < min)

                           min  = parkingdistances[k];

                    d[i][j] = min; 

                }

        }

        return d;

    }

    static int GetDistance(int r1, int c1, int r2, int c2)

    {

        int deltax = r1 - r2;

        deltax = deltax > 0 ? deltax : 0-deltax;

        int deltay = c1 - c2;

        deltay = deltay > 0 ? deltay : 0-deltay;

        return deltax + deltay;        

    }

Generate a recommendation list of courses taken by the social circle of a user. The recommendation must include courses taken by the members of her social circle but not by her. It must be ranked by the number of attendees to the course. A social circle consists only of the persons direct friends and their direct friends.

public List<string> getRankedCourses(string user) {

    var coursePopularity = new Dictionary<string, int>();

    var circle = new List<string>();

    

    var direct = getDirectFriendsForUser(user);

    circle.AddRange(direct);

    foreach (var friend in direct){

        if (friend != user){

        var directForFriend = getDirectFriendsForUser(friend);

        directForFriend.Remove(user);

        circle.AddRange(directForFriend);

        }

    }

    

    foreach (var person in circle)

    {

        var attended = getAttendedCoursesForUser(person);

        foreach(var course in attended)

        {

            if (!coursePopularity.ContainsKey(course))

            {

                coursePopularity.Add(course,1);   

            }

            else

            {

                coursePopularity[course] += 1;   

            }

        }

    }

    

    foreach(var attending in getAttendedCoursesForUser(user))

    {

     coursePopularity.Remove(attending);   

    }

    List<KeyValuePair<string, int>> ranked = coursePopularity.ToList();

    ranked.Sort(

    delegate(KeyValuePair<string, int> pair1,

    KeyValuePair<string, int> pair2)

    {

        return pair1.Value.CompareTo(pair2.Value);

    }

    );

    

    var recommendations = new List<string>();

    foreach (var kvp in ranked)

        recommendations.Add(kvp.Key);

    recommendations.Reverse();

    return recommendations;

}

#codingexercise

test whether an integer is BigIndian or LittleIndian
bool IsLittleIndian()
{
int c = 1;
char * ptr = reinterpret_cast<char*>&c;
return *ptr & 0x1;
}