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Removing strings with duplicate letters from string array

I have array of strings like
string[] A = { "abc", "cccc", "fgaeg", "def" };
I would like to obtain a list or array of strings where any letter appears only one time. I means that "cccc", "fgaeg" will be removed from input array.
I managed to do this but I feel that my way is very messy, unnecessarily complicated and not efficient.
Do you have any ideas to improve this algorythm (possibliy replacing with only one Linq query)?
My code:
var goodStrings = new List<string>();
int i = 0;
foreach (var str in A)
{
var tempArr = str.GroupBy(x => x)
.Select(x => new
{
Cnt = x.Count(),
Str = x.Key
}).ToArray();
var resultArr = tempArr.Where(g => g.Cnt > 1).Select(f => f.Str).ToArray();
if(resultArr.Length==0) goodStrings.Add(A[i]);
i++;
}

You can use Distinct method for every array item and get items with count of distinct items equals to original string length
string[] A = { "abc", "cccc", "fgaeg", "def" };
var result = A.Where(a => a.Distinct().Count() == a.Length).ToList();
You'll get list with abc and def values, as expected

How to sort List according to value in an array

I have
List<string> strs;
double[] values;
where the values array contains the value of each of the string in strs list
Say strs={"abc","def","ghi"}
and values={3,1,2}
this means "abc" has value 3 and so on.
I wish to sort strs and values ordered by values, such that it becomes
strs={"def","ghi","abc"}
values={1,2,3}
Is there any easy way to achieve this?

The Array.Sort method has an overload that takes two arrays and sorts both arrays according to the values in the first array, so make an array out of the list:
string[] strsArr = strs.ToArray();
Then sorting them can't be simpler:
Array.Sort(values, strsArr);
And then back to a list, if you need that:
strs = strsArr.ToList();

You can use Enumerable.Zip, then sort the result, then extract the list of strings.
Something like:
var result = strs.Zip(values, (first, second) => new Tuple<string, double>(first, second))
.OrderBy(x => x.Item2)
.Select(x => x.Item1)
.ToList();

How are you setting up these collections? Or are you given these two parameters?
You could create a StringAndOrder class and use LINQ:
public class StringAndOrder
{
public string String { get; set; }
public double Order { get; set; }
}
List<StringAndOrder> list; //create with this structure instead
var orderedStrings = list.OrderBy(item => item.Order).Select(item => item.String);

var sortedStrs = strs.Select((i, s) => new {Value = values[i], Str = s})
.OrderBy(x => x.Value)
.Select(x => x.Str).ToList();
If you could logically put those values as properties of a class, such as:
class NameAndOrder
{
public string Name;
public int Order;
}
Then it would be better and more organized, and then you could do:
var items = new List<NameAndOrder>(strs.Count);
for (var i = 0; i < strs.Count; i++)
{
items.Add(new NameAndOrder { Name = strs[i], Order = values[i] });
}
items.Sort((a, b) => a.Order.CompareTo(b.Order));

Why Don't you use Dictionary Object..
Dictionary<string, int> dictionary =
new Dictionary<string, int>();
dictionary.Add("cat", 2);
dictionary.Add("dog", 1);
dictionary.Add("llama", 0);
dictionary.Add("iguana", -1);
// Acquire keys and sort them.
var list = dictionary.Keys.ToList();
list.Sort();

var strs = new[] { "abc", "def", "ghi" };
var values = new[] { 3, 1, 2 };
var newArr = strs.Select((s, i) => new { s, i })
.OrderBy(x => values[x.i])
.Select(x => x.s)
.ToArray();

Parse string and order by parsed value

i am trying to build linq expression to solve my problem. I have list of strings
List<string> arr = new List<string>();
arr.Add("<desc><ru>1</ru><en>3</en></desc>");
arr.Add("<desc><ru>2</ru><en>4</en></desc>");
i want to parse every item and order results
fake sample:
arr.Select(ParseItem("en")).OrderBy(x)
then we have two items in ru in order 1,2
Thanks for all and sorry for my bad English
Thanks for all response but how to convert now results to IQueryable
class Test { public string data { get; set; } }
List<Test> arr = new List<Test>();
arr.Add(new Test { data = "<desc><ru>AAA</ru><en>One</en></desc>" });
arr.Add(new Test { data = "<desc><ru>1</ru><en>Two</en></desc>" });
arr.Add(new Test { data = "<desc><ru>22</ru><en>Ab</en></desc>" });
IQueryable<Test> t = arr.AsQueryable();
// here the trouble how to convert to IQueryable<Test>
t = t.Select(s => XElement.Parse(s.data)).Select(x => x.Element("en")).
OrderBy(el => el.Value);
Thanks again

After the question update - this will return your ordered data by <en> node value:
var result = arr
.OrderBy(t=>
XElement.Parse(t.data).Element("en").Value
);
The result valiable is of IOrderedEnumerable<Test> type.

This will produce a list of the values in ru tags (assuming they are integers), ordered by the values in en tags (again, assuming integers).
List<string> items = arr.Select(s => XElement.Parse(s))
.OrderBy(xml => (int)xml.Element("en"))
.Select(xml => (int)xml.Element("ru"))
.ToList();
If you simply want to enumerate, you can omit the ToList call:
foreach (var item in arr.Select(s => XElement.Parse(s))
.OrderBy(xml => (int)xml.Element("en"))
.Select(xml => (int)xml.Element("ru")))
{
// do something with item
}

I'm not sure I've got what the excepted results are, but if you need to select values in en ordered by the value in ru then here it is:
var orderedItems = (
from item in arr
let x = XElement.Parse(item)
let ruValue = (int)x.Element("ru")
let enValue = (int)x.Element("en")
orderby ruValue
select enValue
).ToList();

I don't know if it is too late, but if you are wanting to parse the text and if it is an integer then sort by value otherwise sort by text, then this might help.
You need to define a function like this to enable parsing in LINQ expressions:
Func<string, int?> tryParseInteger = text =>
{
int? result = null;
int parsed;
if (int.TryParse(text, out parsed))
{
result = parsed;
}
return result;
};
Then you can do queries like this:
var xs = new [] { "Hello", "3ff", "4.5", "5", };
var rs =
(from x in xs
select tryParseInteger(x)).ToArray();
// rs == new int?[] { null, null, null, 5, };
In your case you possibly want something like this:
var elements = new []
{
"<desc><ru>AAA</ru></desc>",
"<desc><ru>1</ru></desc>",
"<desc><ru>42</ru></desc>",
"<desc><ru>-7</ru></desc>",
"<desc><ru>BBB</ru></desc>",
"<desc><ru>22</ru></desc>",
};
var query =
from e in elements
let xe = XElement.Parse(e)
let v = xe.Element("ru").Value
orderby v
orderby tryParseInteger(v)
select v;
Which would give you:
{ "AAA", "BBB", "-7", "1", "22", "42" }
If you want to treat non-integers (ie parsed as null) to be zero then change the query by using this line:
orderby tryParseInteger(v) ?? 0
Then you'll get this:
{ "-7", "AAA", "BBB", "1", "22", "42" }
I hope this helps.

create a dictionary using 2 lists using LINQ

I am trying to create a dictionary from 2 lists where one list contains keys and one list contains values. I can do it using for loop but I am trying to find if there is a way of doing it using LINQ.
Sample code will be helpfull. Thanks!!!!

In .NET4 you could use the built-in Zip method to merge the two sequences, followed by a ToDictionary call:
var keys = new List<int> { 1, 2, 3 };
var values = new List<string> { "one", "two", "three" };
var dictionary = keys.Zip(values, (k, v) => new { Key = k, Value = v })
.ToDictionary(x => x.Key, x => x.Value);

List<string> keys = new List<string>();
List<string> values = new List<string>();
Dictionary<string, string> dict = keys.ToDictionary(x => x, x => values[keys.IndexOf(x)]);
This of course assumes that the length of each list is the same and that the keys are unique.
UPDATE: This answer is far more efficient and should be used for lists of non-trivial size.

You can include the index in a Select expression to make this efficient:
var a = new List<string>() { "A", "B", "C" };
var b = new List<string>() { "1", "2", "3" };
var c = a.Select((x, i) => new {key = x, value = b[i]}).ToDictionary(e => e.key, e => e.value );
foreach (var d in c)
Console.WriteLine(d.Key + " = " + d.Value);
Console.ReadKey();

var dic = keys.Zip(values, (k, v) => new { k, v })
.ToDictionary(x => x.k, x => x.v);

You can use this code and working perfectly.
C# Code:
var keys = new List<string> { "Kalu", "Kishan", "Gourav" };
var values = new List<string> { "Singh", "Paneri", "Jain" };
Dictionary<string, string> dictionary = new Dictionary<string, string>();
for (int i = 0; i < keys.Count; i++)
{
dictionary.Add(keys[i].ToString(), values[i].ToString());
}
foreach (var data in dictionary)
{
Console.WriteLine("{0} {1}", data.Key, data.Value);
}
Console.ReadLine();
Output Screen:

A method to count occurrences in a list

Is there a simple way to count the number of occurrences of all elements of a list into that same list in C#?
Something like this:
using System;
using System.IO;
using System.Text.RegularExpressions;
using System.Collections.Generic;
using System.Linq;
string Occur;
List<string> Words = new List<string>();
List<string> Occurrences = new List<string>();
// ~170 elements added. . .
for (int i = 0;i<Words.Count;i++){
Words = Words.Distinct().ToList();
for (int ii = 0;ii<Words.Count;ii++){Occur = new Regex(Words[ii]).Matches(Words[]).Count;}
Occurrences.Add (Occur);
Console.Write("{0} ({1}), ", Words[i], Occurrences[i]);
}
}

How about something like this ...
var l1 = new List<int>() { 1,2,3,4,5,2,2,2,4,4,4,1 };
var g = l1.GroupBy( i => i );
foreach( var grp in g )
{
Console.WriteLine( "{0} {1}", grp.Key, grp.Count() );
}
Edit per comment: I will try and do this justice. :)
In my example, it's a Func<int, TKey> because my list is ints. So, I'm telling GroupBy how to group my items. The Func takes a int and returns the the key for my grouping. In this case, I will get an IGrouping<int,int> (a grouping of ints keyed by an int). If I changed it to (i => i.ToString() ) for example, I would be keying my grouping by a string. You can imagine a less trivial example than keying by "1", "2", "3" ... maybe I make a function that returns "one", "two", "three" to be my keys ...
private string SampleMethod( int i )
{
// magically return "One" if i == 1, "Two" if i == 2, etc.
}
So, that's a Func that would take an int and return a string, just like ...
i => // magically return "One" if i == 1, "Two" if i == 2, etc.
But, since the original question called for knowing the original list value and it's count, I just used an integer to key my integer grouping to make my example simpler.

You can do something like this to count from a list of things.
IList<String> names = new List<string>() { "ToString", "Format" };
IEnumerable<String> methodNames = typeof(String).GetMethods().Select(x => x.Name);
int count = methodNames.Where(x => names.Contains(x)).Count();
To count a single element
string occur = "Test1";
IList<String> words = new List<string>() {"Test1","Test2","Test3","Test1"};
int count = words.Where(x => x.Equals(occur)).Count();

var wordCount =
from word in words
group word by word into g
select new { g.Key, Count = g.Count() };
This is taken from one of the examples in the linqpad

public void printsOccurences(List<String> words)
{
var selectQuery =
from word in words
group word by word into g
select new {Word = g.Key, Count = g.Count()};
foreach(var word in selectQuery)
Console.WriteLine($"{word.Word}: {word.Count}");*emphasized text*
}

This is a version which avoids Linq but uses only slightly more code.
// using System.Collections.Generic;
Dictionary<int, int> oGroups = new Dictionary<int, int>();
List<int> oList = new List<int>() { 1, 2, 3, 4, 5, 2, 2, 2, 4, 4, 4, 1 };
foreach (int iCurrentValue in oList)
{
if (oGroups.ContainsKey(iCurrentValue))
oGroups[iCurrentValue]++;
else
oGroups.Add(iCurrentValue, 1);
}
foreach (KeyValuePair<int, int> oGroup in oGroups)
{
Console.WriteLine($"Value {oGroup.Key} appears {oGroup.Value} times.");
}

this code returns a dictionary that contain the world and the occurrence:
var wordsDic = Words
.GroupBy(p => p)
.ToDictionary(p => p.Key, q => q.Count());

Your outer loop is looping over all the words in the list. It's unnecessary and will cause you problems. Remove it and it should work properly.