Develop Reference

How to check duplicate values in a dictionary

Im having 5 users and 5 services.
I must catch if more than one user(s) have same service. So I created a dictionary:
//JMBGS represents users ids
List<string> multipleJMBGs = new List<string>();
multipleJMBGs.Add(data.jMBG);
multipleJMBGs.Add(data.secondPersonJMBG);
multipleJMBGs.Add(data.thirdPersonJMBG);
multipleJMBGs.Add(data.fourthPersonJMBG);
multipleJMBGs.Add(data.fifthPersonJMBG);
multipleJMBGs.RemoveAll(x => string.IsNullOrEmpty(x));
//object Service has Id property, and I need to check if more than one user has the same service
var serviceForClient = data?.Schedules[0]?.Service;
var serviceForFirstFamilyMember = data?.Schedules[1]?.Service;
var serviceForSecondFamilyMember = data?.Schedules[2]?.Service;
var serviceForThirdFamilyMember = data?.Schedules[3]?.Service;
var serviceForFourthFamilyMember = data?.Schedules[4]?.Service;
Dictionary<string, EmployeeTableDay.ServiceDTO> userService = new Dictionary<string, EmployeeTableDay.ServiceDTO>();
userService.Add(data.jMBG, serviceForClient);
userService.Add(data.secondPersonJMBG, serviceForFirstFamilyMember);
userService.Add(data.thirdPersonJMBG, serviceForSecondFamilyMember);
userService.Add(data.fourthPersonJMBG, serviceForThirdFamilyMember);
userService.Add(data.fifthPersonJMBG, serviceForFourthFamilyMember);
What I want to have as flag (true/false):
different users can have different services
different users can have same services
same users, can not have same service
same users can have multiple services
UPDATE #1:
List<string> multipleJMBGs = new List<string>();
multipleJMBGs.Add(data.jMBG);
multipleJMBGs.Add(data.secondPersonJMBG);
multipleJMBGs.Add(data.thirdPersonJMBG);
multipleJMBGs.Add(data.fourthPersonJMBG);
multipleJMBGs.Add(data.fifthPersonJMBG);
multipleJMBGs.RemoveAll(x => string.IsNullOrEmpty(x));
var countedSchedules = data?.Schedules?.Count();
var serviceIdForClient = 0;
var serviceIdForFirstFamilyMember = 0;
var serviceIdForSecondFamilyMember = 0;
var serviceIdForThirdFamilyMember = 0;
var serviceIdForFourthFamilyMember = 0;
List<int> servicesIds = new List<int>();
if(countedSchedules >= 1 && data?.Schedules[0]?.Service != null)
{
serviceIdForClient = data.Schedules[0].Service.Id;
servicesIds.Add(serviceIdForClient);
}
if (countedSchedules >= 2 && data?.Schedules[1]?.Service != null)
{
serviceIdForFirstFamilyMember = data.Schedules[1].Service.Id;
servicesIds.Add(serviceIdForFirstFamilyMember);
}
if (countedSchedules >= 3 && data?.Schedules[2]?.Service != null)
{
serviceIdForSecondFamilyMember = data.Schedules[2].Service.Id;
servicesIds.Add(serviceIdForSecondFamilyMember);
}
if (countedSchedules >= 4 && data?.Schedules[3]?.Service != null)
{
serviceIdForThirdFamilyMember = data.Schedules[3].Service.Id;
servicesIds.Add(serviceIdForThirdFamilyMember);
}
if (countedSchedules == 5 && data?.Schedules[4]?.Service != null)
{
serviceIdForFourthFamilyMember = data.Schedules[4].Service.Id;
servicesIds.Add(serviceIdForFourthFamilyMember);
}
servicesIds = servicesIds.Where(x => x > 0).ToList();
//because dictionary throws an exception
for (int i = 0; i < countedSchedules; i++)
{
multipleJMBGs[i] = i + " _ " + multipleJMBGs[i];
}
//create dictionary from two lists
var dic = multipleJMBGs.Zip(servicesIds, (k, v) => new { k, v }).ToDictionary(x => x.k, x => x.v);
var duplicateServices = dic.GroupBy(x => x.Value).Where(x => x.Count() > 1)
.Select(x => new { ServiceId = x.Key, Users = x.ToList() });
var duplicateUsers = dic.GroupBy(x => x.Key.Substring(3,x.Key.Length-3)).Where(x => x.Count() > 1)
.Select(x => new { User = x.Key, Services = x.ToList() });
if(duplicateServices > 1 && duplicateUsers.Count > 1)
{
//show a message that it ca't be proceeed further
}
else
{
//continue
}

You can group the services by Id to get information on duplicates:
var groups = data?.Schedules
.Select((service, index) => (service, index))
.GroupBy(x => x.service.Id);
foreach (var g in groups) {
if (g.Count() == 1) {
Console.WriteLine(
$"Service Id {g.Key} exists once for user index {g.First().index}");
} else {
string indexes = String.Join(", ", g.Select(t => t.index.ToString()));
Console.WriteLine(
$"Service Id {g.Key} is shared by user indexes {indexes}");
}
}
If you don't call multipleJMBGs.RemoveAll(...), then the indexes in the users list will match the indexes of the services. So you can easily get the JMBG assigned to a service.
var groups = data?.Schedules
.Select((service, index) => (service, index))
.GroupBy(x => x.service.Id);
foreach (var g in groups) {
if (g.Count() == 1) { // Service is unique
var service = g.First().service;
int index = g.First().index;
string user = multipleJMBGs[index];
...
} else { // Services assigned to more than one user.
var serviceId = g.Key;
var service = g.First().service;
foreach (var t in g) {
int index = t.index;
string user = multipleJMBGs[index];
...
}
...
}
}

Purely answering the question on how to check for duplicates within your dictionary:
You could group the values of your dictionary and look for duplicates that way.
var containsDuplicates = userService.GroupBy(x => x.Value).Any(x => x.Count() > 1);
If you want to actually see which services are used multiple times by which users, create the following grouping:
var duplicateServices = userService.GroupBy(x => x.Value).Where(x => x.Count() > 1)
.Select(x => new { Service = x.Key, Users = x.ToList() });
UPDATE #1:
You don't necessarily have to group up both of these lists if you just need to check if any of the two contain duplicates.
We could simply compare the total count of the lists with the count of the list when we remove all possible duplicates:
var duplicateServices = countedSchedules != data?.Schedules?.Distinct().Count();
var duplicateUsers = multipleJMBGs.Count() != multipleJMBGs.Distinct().Count();
UPDATE #2:
Sounds like you want to join the two lists together and not necessarily convert it to a dictionary, what we want to do instead is create a new List so we can group that on the combination of the two properties.
var containsDuplicates = multipleJMBGs.Zip(serviceIds, (JMBG, serviceId) => new { JMBG, serviceId })
.Where(x => !string.IsNullOrEmpty(x.JMBG) && x.serviceId > 0) // Filter AFTER zipping the two lists together
.GroupBy(x => x).Any(x => x.Count() > 1);
Do be aware that you are removing elements in both lists, meaning that the order might not be correct. You could instead add a Where clause after you zip the lists like in the example above.

how to arrange the item of a list into series arrangement

I have a list of data which contains of random data with combination of string and number:
List<String> Data1 = new List<String>()
{
"1001A",
"1002A",
"1003A",
"1004A",
"1015A",
"1016A",
"1007A",
"1008A",
"1009A",
};
I want this data to arrange into series like this:
1001A - 1004A, 1007A - 1009A, 1015A, 1016A
for every more than 2 counts of data series the output shall be have "-" between the first count and the last count of series, the other non series data will be just added to the last part and all together will separated by ",".
I'd already made some codes only to arrange the data series by the last char of it:
string get_REVISIONMARK = "A";
var raw_serries = arrange_REVISIONSERIES.Where(p => p[p.Length - 1].ToString() == get_REVISIONMARK) .OrderBy(p => p[p.Length - 1) .ThenBy(p => p.Substring(0, p.Length - 1)).ToList();
just ignore the last char I'd already have function for that, and my problem only about the arrangement of the numbers, the length of data is not fixed. for other example of output "1001A - 1005A, 301A, 32A"
I had another sample of my codes this works fine to me, but for me its so lazy code.
for (int c1 = 0; c1 < list_num.Count; c1++)
{
if (list_num[c1] != 0)
{
check1 = list_num[c1];
for (int c2 = 0; c2 < list_num.Count; c2++)
{
if (check1 == list_num[c2])
{
list_num[c2] = 0;
check1 += 1;
list_series.Add(arrange_REVISIONSERIES[c2]);
}
}
check1 = 0;
if (list_series.Count > 2)
{
res_series.Add(list_series[0] + " to " +list_series[list_series.Count - 1]);
list_series.Clear();
}
else
{
if (list_series.Count == 1)
{
res_series.Add(list_series[0]);
list_series.Clear();
}
else
{
res_series.Add(list_series[0] + "," + list_series[1]);
list_series.Clear();
}
}
}
}
var combine_res = String.Join(",", res_series);
MessageBox.Show(combine_res);
this codes work fine for the series number ...

A possible solution (working with current set of values), Please follow the steps below
Declare a class level string list as
public List<String> data_result = new List<string>();
Create a function to iterate through input string list (input string declared inside, named 'data')
public void ArrangeList()
{
List<String> data = new List<string>() { "1001A", "1002A", "1003A",
"1004A", "1015A", "1016A", "1007A", "1008A", "1009A", "1017A" };
List<int> data_int = data.Select(a => Convert.ToInt32(a.Substring(0,
a.Length - 1))).OrderBy(b => b).ToList();
int initializer = 0, counter = 0;
int finalizer = 0;
foreach (var item in data_int)
{
if (initializer == 0)
{ initializer = item; continue; }
else
{
counter++;
if (item == initializer + counter)
finalizer = item;
else
{
LogListing(initializer, finalizer);
initializer = item;
finalizer = item;
counter = 0;
}
}
}
LogListing(initializer, finalizer);
}
Create a function which just logs the result into data_result string list.
public void LogListing(int initializer, int finalizer)
{
if (initializer != finalizer)
{
if (finalizer == initializer + 1)
{
data_result.Add(initializer + "A");
data_result.Add(finalizer + "A");
}
else
data_result.Add(initializer + "A - " + finalizer + "A");
}
else
data_result.Add(initializer + "A");
}
It perfectly generates the result list as
Thumb-up if you like

A linqy solution:
char get_REVISIONMARK = 'A';
var res = arrange_REVISIONSERIES.Select(s => new { Rev = s[s.Length - 1], Value = int.Parse(s.Substring(0, s.Length - 1)), Org = s })
.Where(d => d.Rev == get_REVISIONMARK).OrderBy(d => d.Value)
.Select((val, ind) => new { Index = ind, Org = val.Org, Value = val.Value }).GroupBy(a => a.Value - a.Index)
.Select(gr=>gr.ToList()).OrderBy(l=>l.Count > 2 ? 0 : 1 ).Aggregate(new List<string>(), (list, sublist) =>
{
if (sublist.Count > 2)
list.Add(sublist[0].Org + " - " + sublist[sublist.Count - 1].Org);
else
list.AddRange(sublist.Select(a => a.Org));
return list;
});
The first lines are basically the same as the code you already have (filter on revision and sort), but with the difference that the subvalues are stored in an anonymous type. You could do the same on the pre ordered list, but since splitting the string would be done twice I've included it in the total.
Then a select with index (.Select((val, ind) =>) is made to get value/index pairs. This is done to be able to get the sequences based on an old t-sql row_number trick: for each 'group' the difference between value and index is the same .GroupBy(a => a.Value - a.Index)
After that, normally you'd be as good as done, but since you only want to make sequences of 2 and longer, we make sublists out of the groupby values and do the ordering beforehand to make sure the ranges come for the eventual single elements .Select(gr=>gr.ToList()).OrderBy(l=>l.Count > 2 ? 0 : 1 )
Finally, the list is created of the groups. Several options, but I like to use Aggregate for that. The seed is the resulting list, and the aggregate simply adds to that (where subranges > 2 are cummulated and for single elements and pairs, the single elements are added)

I'm making two assumptions:
The list is already ordered
The non-numeric characters can be ignored
You will get the results in the results variable:
void Main()
{
List<String> Data1 = new List<String>()
{
"1001A",
"1002A",
"1003A",
"1004A",
"1015A",
"1016A",
"1007A",
"1008A",
"1009A",
};
var accu = new List<List<Tuple<int, string>>>();
foreach (var data in Data1)
{
if (accu.Any(t => t.Any(d => d.Item1 == (ToInt(data) - 1))))
{
var item = accu.First(t => t.Any(d => d.Item1 == (ToInt(data) - 1)));
item.Add(new Tuple<int, string>(ToInt(data), data));
}
else
{
accu.Add(new List<Tuple<int, string>>{ new Tuple <int, string>(ToInt(data), data)});
}
}
var results = new List<string>();
results.AddRange(accu.Where(g => g.Count > 2).Select(g => string.Format("{0} - {1}", g.First().Item2, g.Last().Item2)));
results.AddRange(accu.Where(g => g.Count <= 2).Aggregate(new List<string>(), (total, current) => { total.AddRange(current.Select(i => i.Item2)); return total; } ));
}
private static Regex digitsOnly = new Regex(#"[^\d]");
public static int ToInt(string literal)
{
int i;
int.TryParse(digitsOnly.Replace(literal, ""), out i);
return i;
}

So given your starting data:
List<String> arrange_REVISIONSERIES = new List<String>()
{
"1001A",
"1002A",
"1003A",
"1004A",
"1015A",
"1016A",
"1007A",
"1008A",
"1009A",
};
I do this first:
var splits =
arrange_REVISIONSERIES
.Select(datum => new
{
value = int.Parse(datum.Substring(0, datum.Length - 1)),
suffix = datum.Substring(datum.Length - 1, 1),
})
.OrderBy(split => split.suffix)
.ThenBy(split => split.value)
.ToArray();
That's basically the same as your raw_serries, but orders the number part as a number. It seems to me that you need it as a number to make the range part work.
I then do this to compute the groupings:
var results =
splits
.Skip(1)
.Aggregate(
new[]
{
new
{
start = splits[0].value,
end = splits[0].value,
suffix = splits[0].suffix
}
}.ToList(),
(a, s) =>
{
if (a.Last().suffix == s.suffix && a.Last().end + 1 == s.value)
{
a[a.Count - 1] = new
{
start = a.Last().start,
end = s.value,
suffix = s.suffix
};
}
else
{
a.Add(new
{
start = s.value,
end = s.value,
suffix = s.suffix
});
}
return a;
})
.Select(r => r.start == r.end
? String.Format("{0}{1}", r.end, r.suffix)
: (r.start + 1 == r.end
? String.Format("{0}{2}, {1}{2}", r.start, r.end, r.suffix)
: String.Format("{0}{2} - {1}{2}", r.start, r.end, r.suffix)))
.ToArray();
And finally, this to create a single string:
var result = String.Join(", ", results);
That gives me:
1001A - 1004A, 1007A - 1009A, 1015A, 1016A
This code nicely works with data containing different suffixes.

Increment in LINQ Query

Hello I have the following code which returns me List of type Listitem. I want to increase the value by one for every ListItem Selected.
public static List<System.Web.UI.WebControls.ListItem> GetMyCompassTUTListContent(List<int> ContentID, Int32 CountryID)
{
int Counter = 0;
List<System.Web.UI.WebControls.ListItem> litems = new List<System.Web.UI.WebControls.ListItem>();
using (DbDataContext objContext = new DbDataContext())
{
if (CountryID == (int)MyCompassBLL.Constants.Country.Australia)
{
litems = objContext.Contents.Where(x => ContentID.Contains(x.ID)).Select(x => new System.Web.UI.WebControls.ListItem { Text = x.Text, y = (y + 1) }).ToList();
}
else
{
litems = objContext.ContentCountries.Where(x => ContentID.Contains(x.ContentID) && x.CountryID == CountryID).Select(x => new System.Web.UI.WebControls.ListItem { Text = x.Text, Value = (Counter + 1).ToString() }).ToList();
}
}
return litems;
}
Please help me in this. I am not able to that since I am not able to find the way of how to reassign value to variable counter after increment.
Thanks in advance

There is an overload of Select that also provides the index of the current item. You can use that. However, most DB query providers don't support it, so you'll need to do your DB query, then ensure that the Enumerable overload of Select is called to add the index:
public static List<ListItem> GetMyCompassTUTListContent(
List<int> ContentID, Int32 CountryID)
{
//Note this is IEnumerable, not IQueryable, this is important.
IEnumerable<string> query;
using (DbDataContext objContext = new DbDataContext())
{
if (CountryID == (int)MyCompassBLL.Constants.Country.Australia)
{
query = objContext.Contents.Where(x => ContentID.Contains(x.ID))
.Select(x => x.Text);
}
else
{
query = objContext.ContentCountries
.Where(x => ContentID.Contains(x.ContentID)
&& x.CountryID == CountryID)
.Select(x => x.Text);
}
return query.Select((text, index) => new ListItem
{
Text = text,
Value = (index + 1).ToString(),
})
.ToList();
}
}

Use ++Counter instead of ( Counter + 1)
[UPDATE]
try to increment your Counter before put it into the Select():
else
{
Counter++;
litems = objContext.ContentCountries.Where(x => ContentID.Contains(x.ContentID) && x.CountryID == CountryID).Select(x => new System.Web.UI.WebControls.ListItem { Text = x.Text, Value = Counter.ToString() }).ToList();
}

how can i count duplicates in a list and change the item value

I have a program that generates 3 lists based on the contents of a text file. Now I want to look at a list and if there's an item in it more than once, I'd like to change the value to "number in list x item" and remove the duplicates from the list.
Here is the code I use to open and split up the file into the lists:
private void open_Click(object sender, EventArgs e)
{
if (inputFile.ShowDialog() == DialogResult.OK)
{
var reader = new StreamReader(File.OpenRead(inputFile.FileName));
while (!reader.EndOfStream)
{
string line = reader.ReadLine();
if (string.IsNullOrEmpty(line)) continue;
if (line.StartsWith("#main"))
{
deck = "main";
}
if (deck == "main")
{
if (!line.StartsWith("#"))
{
int cardid = Convert.ToInt32(line.Substring(0));
MainDeck.Items.Add(Program.CardData[cardid].Name);
}
}
if (line.StartsWith("#extra"))
{
deck = "extra";
}
if (deck == "extra")
{
if (!line.StartsWith("#extra") && !line.StartsWith("!side"))
{
int cardid = Convert.ToInt32(line.Substring(0));
ExtraDeck.Items.Add(Program.CardData[cardid].Name);
}
}
if (line.StartsWith("!side"))
{
deck = "side";
}
if (deck == "side")
{
if (!line.StartsWith("!side"))
{
int cardid = Convert.ToInt32(line.Substring(0));
SideDeck.Items.Add(Program.CardData[cardid].Name);
}
}
}
reader.Close();
GenerateCode();
}
}
In other words say the item "hello" is in the list 3 times: I want to change it to be in the list only once and say "3x hello".

Use Enumerable.Distinct to remove the duplicates:
MainDeck = MainDeck.Distinct().ToList();
ExtraDeck = ExtraDeck.Distinct().ToList();
SideDeck = SideDeck.Distinct().ToList();
If you want to count the duplicates first:
int mainDeckDups = MainDeck.Count - MainDeck.Distinct().Count();
int extraDeckDups = ExtraDeck.Count - ExtraDeck.Distinct().Count();
int sideDeckDups = SideDeck.Count - SideDeck.Distinct().Count();
If you really want to show how many times an item was in the list you could use Enumerable.GroupBy, e.g.:
var mainDeckGroups = MainDeck.GroupBy(s => s)
.Select(g => new { Item = g.Key, Count = g.Count() })
.Where(x => x.Count > 1)
.OrderByDescending(x => x.Count);
foreach (var dup in mainDeckGroups)
Console.WriteLine("{0}x {1}", dup.Count, dup.Item);
// other lists ...

Something like:
var g = MainDeck.Items.GroupBy(i => i).Select(x => x.Count() +"x " + x.Key);
You can filter it out if you want to count only the word "main" there. Follow the same for other lists..
The query is not evaluated at that point. Do a .ToList() or .ToArray() to let that happen on g.

If you want to preserve order of items in the list (assuming list contains the possible duplicates)
var data = list.Select(r => result.Count(i => i == r) + "x " + r).ToList();
and just slightly modify it to have "Hello" instead of "1x Hello".

You can try it as well.
var list = new List<string> { "Hello", "World", "Hello", "Great", "World" };
var query = list.GroupBy(s => s)
.Select(g => new { Value = g.Key, Count = g.Count() });
Then,
var resultList = query.Select(result => string.Format("{0}x {1}", result.Count, result.Value)).ToList();
or above code can be replaced as below for more clarity
foreach (var result in query)
resultList.Add(string.Format("{0}x {1}", result.Count, result.Value));
Hope it helps.

Grouping each 500 elements of array according to array elements

I have an array of 2000 strings. The strings are: "art", "economy", "sport" and "politic". I want to group each 500 elements and get their counts
Could anyone help please?

Another solution:
var count = 0;
var dictionaries =
strings.GroupBy(s => count++ / 500)
.Select(g => g.Distinct().ToDictionary(k => k, k => g.Count(s => s == k)))
.ToList();
This will create a List<Dictionary<string, int>>. Each dictionary represents a tally of 500 elements (or possibly less for the last dictionary), where the keys are strings and the values are the number of occurrences of the string among the 500 elements the dictionary represents.
There is no requirement to hardcode all the possible values that may be encountered.
For the maximum possible performance you can also use this version:
var count = 0;
var dictionaries =
strings.GroupBy(s => count++ / 500)
.Select(g => g.Aggregate(
new Dictionary<string, int>(),
(d, w) => { d[w] = (d.ContainsKey(w) ? d[w] + 1 : 1); return d; })
)
.ToList();
This version iterates over each element in your source array exactly once. The output is in the same format as the first version.

var result = strings.Select((s, i) => new { s, i })
.GroupBy(x => x.i / 500)
.Select(x => x.GroupBy(y => y.s)
.Select(z => new {
Name=z.Key,
Count=z.Count()
}).ToList())
.ToList();

Try
var grouping = Enumerable.Range(0,2000)
.Select(i => i / 500)
.Zip(Strings, (i,s) => new { Group = i, Str = s})
.GroupBy(anon => anon.Group,
anon => anon.Str,
(key,g) => new
{
Key = key,
Art = g.Count(str => str == "art"),
Economy = g.Count(str => str == "economy"),
Politic = g.Count(str => str == "politic"),
Sport= g.Count(str => str == "sport")
});
foreach(anon in grouping)
{
//textbox logic OP will have to change to suit
TextBox1.WriteLine(String.Format("Group: {0}", anon.Key));
TextBox1.WriteLine(String.Format("Art: {0}",anon.Art));
TextBox1.WriteLine(String.Format("Economy: {0}",anon.Economy ));
TextBox1.WriteLine(String.Format("Politic: {0}",anon.Politic ));
TextBox1.WriteLine(String.Format("Sport: {0}",anon.Sport));
}
Alternatively (as per Snowbear)
var grouping = Strings.Select((s,i) => new { Group = i / 500, Str = s})
.GroupBy(anon => anon.Group,
anon => anon.Str,
(key,g) => new
{
Key = key,
Art = g.Count(str => str == "art"),
Economy = g.Count(str => str == "economy"),
Politic = g.Count(str => str == "politic"),
Sport= g.Count(str => str == "sport")
});
foreach(anon in grouping)
{
//textbox logic OP will have to change to suit
TextBox1.WriteLine(String.Format("Group: {0}",anon.Key + 1));
TextBox1.WriteLine(String.Format("Art: {0}",anon.Art));
TextBox1.WriteLine(String.Format("Economy: {0}",anon.Economy ));
TextBox1.WriteLine(String.Format("Politic: {0}",anon.Politic ));
TextBox1.WriteLine(String.Format("Sport: {0}",anon.Sport));
}

int CountElementsInGroup = 500;
//from 500 to 1000
int NumberGroup = 2;
string[] GroupTypes = new string[4] { "art", "economy", "sport", "politic" };
//Fill example array
string[] arr = new string[2000];
Random rand = new Random();
for (int i = 0; i < arr.Length;i++ )
arr[i] = GroupTypes[rand.Next(0, 3)];
var res = (from p in arr.Skip((NumberGroup - 1) * CountElementsInGroup).Take(CountElementsInGroup)
group p by p into g
select new GroupCountClass { GroupName = g.Key, GroupCount = g.Count() });
textBox1.Text = "";
foreach (GroupCountClass c in res)
{
textBox1.Text += String.Format("GroupName:{0} Count:{1};",c.GroupName,c.GroupCount);
}