C # (String.StartsWith &&! String.EndsWith &&! String.Contains) using a list

Question

I am new to C # and I am having problems.

I have 2 lists, 2 rows and a getCombinations (string) method that returns all combinations of a string as List;

How to check if a subjectStrings element has StartWith && EndsWith && Contains (or! StartWith & EndsWith & & Contains, etc.) for each combination of startswithString, endswithString and containsString?

Here is my code in StartWith & &! EndsWith (if you want to run it: http://ideone.com/y8JZkK )

    using System;
    using System.Collections.Generic;
    using System.Linq;

    public class Test
    {
            public static void Main()
            {
                    List<string> validatedStrings = new List<string>();
                    List<string> subjectStrings = new List<string>()
                    {
                            "con", "cot", "eon", "net", "not", "one", "ten", "toe", "ton",
                                    "cent", "cone", "conn", "cote", "neon", "none", "note", "once", "tone",
                                    "cento", "conte", "nonce", "nonet", "oncet", "tenon", "tonne",
                                    "nocent","concent", "connect"
                    }; //got a more longer wordlist

                    string startswithString = "co";
                    string endswithString = "et";

                    foreach(var z in subjectStrings)
                    {
                        bool valid = false;
                        foreach(var a in getCombinations(startswithString))
                        {
                            foreach(var b in getCombinations(endswithString))
                            {
                                if(z.StartsWith(a) && !z.EndsWith(b))
                                {
                                        valid = true;
                                        break;
                                }
                            }
                            if(valid)
                            {
                                break;
                            }
                        }
                        if(valid)
                        {
                            validatedStrings.Add(z);
                        }
                    }

                    foreach(var a in validatedStrings)
                    {
                            Console.WriteLine(a);
                    }
                    Console.WriteLine("\nDone");
            }


            static List<string> getCombinations(string s)
            {
                    //Code that calculates combinations
                    return Permutations.Permutate(s);
            }
    }

    public class Permutations
    {
            private static List<List<string>> allCombinations;

            private static void CalculateCombinations(string word, List<string> temp)
            {
                    if (temp.Count == word.Length)
                    {
                            List<string> clone = temp.ToList();
                            if (clone.Distinct().Count() == clone.Count)
                            {
                                    allCombinations.Add(clone);
                            }
                            return;
                    }

                    for (int i = 0; i < word.Length; i++)
                    {
                            temp.Add(word[i].ToString());
                            CalculateCombinations(word, temp);
                            temp.RemoveAt(temp.Count - 1);
                    }
            }

            public static List<string> Permutate(string str)
            {
                    allCombinations = new List<List<string>>();
                    CalculateCombinations(str, new List<string>());
                    List<string> combinations = new List<string>();
                    foreach(var a in allCombinations)
                    {
                            string c = "";
                            foreach(var b in a)
                            {
                                    c+=b;
                            }
                            combinations.Add(c);
                    }
                    return combinations;
            }
    }

Output:

    con 
    cot
    cone
    conn
    cote <<<
    conte <<<
    concent
    connect

    Done

if (z.StartsWith (a) &! z.EndsWith (b)) var b may be "et" and "te", but cote and conte end with "te", why is it still added to my checked lines?

.

Answer 1

z.StartsWith(a) && !z.EndsWith(b)

z ="cote"
a ="co"
b ="te"

z "co" z "te", , cote

var sw =getCombinations(startswithString);
var ew = getCombinations(endswithString);


var result = subjectStrings.Where(z=> 
    sw.Any(x=>z.StartsWith(x) && 
        !ew.Any(y=>z.EndsWith(y))))
        .ToList();

DEMO

:

con
cot
cone
conn
concent
connect

Answer 2

                            foreach(var b in getCombinations(endswithString))
                        {
                            if(z.StartsWith(a) && !z.EndsWith(b))
                            {
                                    valid = true;
                                    break;
                            }
                        }

true, ! z.EndsWith(b), . "cote" "et", , valid true . , "cote" . "conte".

:

    List<string> startsWithCombination = getCombinations("co");
    List<string> endsWithCombination = getCombinations("et");

    foreach (var z in subjectStrings)
    {
        bool isStartMatchFound = startsWithCombination.Any(b => z.StartsWith(b));

        if (isStartMatchFound)
        {
            bool isEndMatchFound = endsWithCombination.Any(b => z.EndsWith(b));

            if (!isEndMatchFound)
            {
                validatedStrings.Add(z);
            }
        }
    }