Added solution to problem 17

ProjectEulerCS/ProblemSelection.cs

@@ -31,7 +31,7 @@ namespace ProjectEulerCS{
 		//Holds the valid problem numbers
 		private static readonly List<int> _PROBLEM_NUMBERS = new List<int>()
 				{ 0,  1,  2,  3,  4,  5,  6,  7,  8,  9,
-				 10, 11, 12, 13, 14, 15, 16};
+				 10, 11, 12, 13, 14, 15, 16, 17};
 		public static System.Collections.Generic.List<int> PROBLEM_NUMBERS{
 			get { return _PROBLEM_NUMBERS; }
 		}
@@ -56,6 +56,7 @@ namespace ProjectEulerCS{
 				case 14: problem = new Problem14(); break;
 				case 15: problem = new Problem15(); break;
 				case 16: problem = new Problem16(); break;
+				case 17: problem = new Problem17(); break;
 			}
 			return problem;
 		}

ProjectEulerCS/Problems/Problem17.cs

@@ -0,0 +1,198 @@
+//ProjectEuler/ProjectEulerCS/src/Problems/Problem17.cs
+//Matthew Ellison
+// Created: 08-25-20
+//Modified: 08-25-20
+//If all the numbers from 1 to 1000 (one thousand) inclusive were written out in words, how many letters would be used?
+//Unless otherwise listed all non-standard includes are my own creation and available from https://bibucket.org/Mattrixwv/CSClasses
+/*
+	Copyright (C) 2020  Matthew Ellison
+
+	This program is free software: you can redistribute it and/or modify
+	it under the terms of the GNU Lesser General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU Lesser General Public License for more details.
+
+	You should have received a copy of the GNU Lesser General Public License
+	along with this program.  If not, see <https://www.gnu.org/licenses/>.
+*/
+
+
+using System;
+
+
+namespace ProjectEulerCS.Problems{
+	public class Problem17 : Problem{
+		//Variables
+		//Static variables
+		private const int START_NUM = 1;	//This is the smallest number to get the words of
+		private const int STOP_NUM = 1000;	//This is the largest number to get the words of
+		//Instance variables
+		private long letterCounter;	//This is the cumulative number of letters in the words of the numbers
+		public long LetterCount{
+			get{
+				if(!solved){
+					throw new Unsolved();
+				}
+				return letterCounter;
+			}
+		}
+
+		//Functions
+		//Constructor
+		public Problem17() : base("If all the numbers from 1 to 1000 (one thousand) inclusive were written out in words, how many letters would be used?"){
+			letterCounter = 0;
+		}
+		//Operational functions
+		//Solve the problem
+		public override void Solve(){
+			//If the problem has already been solved do nothing and end the function
+			if(solved){
+				return;
+			}
+
+			//Start the timer
+			_timer.Start();
+
+			//Start with 1 and increment
+			for(int num = START_NUM;num <= STOP_NUM;++num){
+				//Pass the number to a function that will create a string for the number
+				string currentNumString = GetStringFromNum(num);
+				//Pass the string to the function that will count the number of letters in it, ignoring whitespace and punctuation and add that number to the running tally
+				letterCounter += GetNumberChars(currentNumString);
+			}
+
+			//Stop the timer
+			_timer.Stop();
+
+			//Throw a flag to show the problem is solved
+			solved = true;
+
+			//Save the results
+			_result = "The sum of all the letters in all the numbers " + START_NUM + "-" + STOP_NUM + " is " + letterCounter;
+		}
+		//Reset the problem so it can be run again
+		public override void Reset(){
+			base.Reset();
+			letterCounter = 0;
+		}
+		//This function makes a word out of the number passed into it
+		private string GetStringFromNum(int number){
+			string numberString = "";
+			//Starting with the largest digit create a string based on the number passed in
+			//Check for negative
+			if(number < 0){
+				numberString += "negative ";
+			}
+
+			//Check if the number is zero
+			if(number == 0){
+				numberString += "zero";
+			}
+
+			//Start with the thousands place
+			if((number / 1000D) >= 1D){
+				numberString += GetStringFromNum((int)System.Math.Floor(number / 1000D));
+				numberString += " thousand";
+				number -= (((int)Math.Floor(number / 1000D)) * 1000);
+			}
+
+			//Check the hundreds place
+			if((number / 100D) >= 1D){
+				numberString += GetStringFromNum((int)Math.Floor(number / 100D));
+				numberString += " hundred";
+				number -= (((int)Math.Floor(number / 100D)) * 100);
+			}
+
+			//Insert an and if there is need
+			if((numberString.Length > 0) && (number > 0)){
+				numberString += " and ";
+			}
+
+			//Check for tens place
+			if((number / 10D) >= 2D){
+				//For the tens you need to do something special
+				int tensPlace = (int)Math.Floor(number / 10D);
+				switch(tensPlace){
+					case 9: numberString += "ninety"; break;
+					case 8: numberString += "eighty"; break;
+					case 7: numberString += "seventy"; break;
+					case 6: numberString += "sixty"; break;
+					case 5: numberString += "fifty"; break;
+					case 4: numberString += "forty"; break;
+					case 3: numberString += "thirty"; break;
+					case 2: numberString += "twenty"; break;
+				}
+				number -= (tensPlace * 10);
+				//If there is something left in the number you will need a dash to separate the tens and ones place
+				if(number > 0){
+					numberString += "-";
+				}
+			}
+			//Check for teens
+			else if((number / 10D) >= 1D){
+				int onesPlace = (number % 10);
+				switch(onesPlace){
+					case 9: numberString += "nineteen"; break;
+					case 8: numberString += "eighteen"; break;
+					case 7: numberString += "seventeen"; break;
+					case 6: numberString += "sixteen"; break;
+					case 5: numberString += "fifteen"; break;
+					case 4: numberString += "fourteen"; break;
+					case 3: numberString += "thirteen"; break;
+					case 2: numberString += "twelve"; break;
+					case 1: numberString += "eleven"; break;
+					case 0: numberString += "ten"; break;
+				}
+				//If this was hit the number was completed
+				number = 0;
+			}
+
+			//Check for the ones place
+			if(number >= 1){
+				switch(number){
+					case 9: numberString += "nine"; break;
+					case 8: numberString += "eight"; break;
+					case 7: numberString += "seven"; break;
+					case 6: numberString += "six"; break;
+					case 5: numberString += "five"; break;
+					case 4: numberString += "four"; break;
+					case 3: numberString += "three"; break;
+					case 2: numberString += "two"; break;
+					case 1: numberString += "one"; break;
+				}
+				//If this was hit the number was completed
+				number = 0;
+			}
+
+			if(number != 0){
+				throw new mee.Exceptions.InvalidResult("The number was not reduced to 0!");
+			}
+
+			//Return the string
+			return numberString;
+		}
+		//This counts the number of letters in the string that is passed in (ignoring numbers and punctuation)
+		private int GetNumberChars(String number){
+			int sumOfLetters = 0;
+			//Start at location 0 and count the number of letters, ignoring punctuation and whitespace
+			for(int location = 0;location < number.Length;++location){
+				if(Char.IsLetter(number[location])){
+					sumOfLetters += 1;
+				}
+			}
+
+			//Return the number of letters
+			return sumOfLetters;
+		}
+	}
+}
+
+/* Result:
+The sum of all the letters in all the numbers 1-1000 is 21124
+It took an average of 208.222 microseconds to run this problem through 100 iterations
+*/