Joel Lewis

Joel Lewis

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What's wrong with this code?

Jun 21 2012 8:58 AM
Recently went to a job interview and I have been told that the below solution is not good. Unfortunately they did not give me a feedback. Can anyone please review my code and see anything obviously wrong here?

Interview Question:

The file hockey.csv contains the results from the Hockey Premier League. The columns 'F' and 'A' contain the total number of goals scored for and against each team in that season (so Alabama scored 79 goals against opponents, and had 36 goals scored against them).

Write a program to print the name of the team with the smallest difference in 'for' and 'against' goals.

 hockey.csv looks like this (sorry about the column headings)

Team  P W L D F - A Pts
Alabama 38 26 9 3 79 - 36 87
Washinton 38 24 8 6 67 - 30 80
Indiana 38 24 5 9 87 - 45 77
Newcastle 38 21 8 9 74 - 52 71
Florida 38 18 12 8 53 - 37 66
Chelsea 38 17 13 8 66 - 38 64
West_Ham 38 15 8 15 48 - 57 53
New York 38 12 14 12 46 - 47 50
Sunderland 38 10 10 18 29 - 51 40
-------------------------------------------------------
Lova 38 9 9 20 41 - 64 36
Nevada 38 8 6 24 33 - 63 30
Boston 38 5 13 20 30 - 64 28

My solution:

The console App:

 class Program
    {
        static void Main(string[] args)
        {
            string path = @"C:\....<path to the hockey.csv file>;

            var resultEvaluator = new ResultEvaluator(string.Format(@"{0}\{1}",path, "football.csv"));
            var team = resultEvaluator.GetTeamSmallestDifferenceForAgainst();

            Console.WriteLine(
                string.Format("Smallest difference in 'for' and 'against' goals > TEAM: {0}, GOALS DIF: {1}",
                team.Name, team.Difference ));

            Console.ReadLine();
        }
    }



public class Team
    {
        public Team(string name, int against, int @for)
        {
            Name = name;
            Against = against;
            For = @for;
        }

        public string Name { get; private set; }

        public int Against { get; private set; }

        public int For { get; private set; }

        public int Difference
        {
            get { return (For - Against); }
        }
    }



public interface IResultEvaluator
    {
        Team GetTeamSmallestDifferenceForAgainst();
    }

 public interface ICsvExtractor
    {
        DataTable GetDataTable(string csvFilePath);
    }


 public class ResultEvaluator : IResultEvaluator
    {
        private static DataTable leagueDataTable;
        private readonly string filePath;
        private readonly ICsvExtractor csvExtractor;

        public ResultEvaluator(string filePath){
            this.filePath = filePath;
            csvExtractor = new CsvExtractor();
        }

        private DataTable LeagueDataTable{
            get
            {
                if (leagueDataTable == null)
                {
                    leagueDataTable = csvExtractor.GetDataTable(filePath);
                }

                return leagueDataTable;
            }
        }

        public Team GetTeamSmallestDifferenceForAgainst() {
            var teams = GetTeams();
            var lowestTeam = teams.OrderBy(p => p.Difference).First();
            return lowestTeam;
        }

        private IEnumerable<Team> GetTeams() {
            IList<Team> list = new List<Team>();

            foreach (DataRow row in LeagueDataTable.Rows)
            {
                var name = row["Team"].ToString().Remove(0, 3).Trim();
                var @for = int.Parse(row["F"].ToString());
                var against = int.Parse(row["A"].ToString());
                var team = new Team(name, against, @for);
                list.Add(team);
            }

            return list;
        }
    }

public class CsvExtractor : ICsvExtractor
    {
        public DataTable GetDataTable(string csvFilePath)
        {
            var lines = File.ReadAllLines(csvFilePath);

            string[] fields;

            fields = lines[0].Split(new[] { ',' });
            int columns = fields.GetLength(0);
            var dt = new DataTable();

            //always assume 1st row is the column name.
            for (int i = 0; i < columns; i++)
            {
                dt.Columns.Add(fields[i].ToLower(), typeof(string));
            }

            DataRow row;
            for (int i = 1; i < lines.GetLength(0); i++)
            {
                fields = lines[i].Split(new char[] { ',' });

                if (fields.Count() == 1) // to elimate the bad data : temp solution
                {
                    continue;
                }

                row = dt.NewRow();
                for (int f = 0; f < columns; f++)
                    row[f] = fields[f];
                dt.Rows.Add(row);
            }

            return dt;
        }


The interviewer was only interested in the structure/design of the code and whether I can produce the correct result (i.e lowest difference). Can anyone please tell me  any issues in the solution above? Much appreciated.


Answers (1)