Added solution to problem 38

ProjectEulerCS/ProblemSelection.cs

@@ -1,10 +1,10 @@
 //ProjectEuler/ProjectEulerCS/src/ProblemSelection.cs
 //Matthew Ellison
 // Created: 08-21-20
-//Modified: 06-05-21
+//Modified: 10-11-21
 //This class holds all of the functions needed to handle a problem
 /*
-	Copyright (C) 2020  Matthew Ellison
+	Copyright (C) 2021  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
@@ -33,8 +33,8 @@ namespace ProjectEulerCS{
 				{ 0,  1,  2,  3,  4,  5,  6,  7,  8,  9,
 				 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
 				 20, 21, 22, 23, 24, 25, 26, 27, 28, 29,
-				 30, 31, 32, 33, 34, 35, 36, 37, 67};
+				 30, 31, 32, 33, 34, 35, 36, 37, 38, 67};
-		public static System.Collections.Generic.List<int> PROBLEM_NUMBERS{
+		public static List<int> PROBLEM_NUMBERS{
 			get { return _PROBLEM_NUMBERS; }
 		}
 
@@ -79,6 +79,7 @@ namespace ProjectEulerCS{
 				case 35 : problem = new Problem35(); break;
 				case 36 : problem = new Problem36(); break;
 				case 37 : problem = new Problem37(); break;
+				case 38 : problem = new Problem38(); break;
 				case 67 : problem = new Problem67(); break;
 			}
 			return problem;

ProjectEulerCS/Problems/Problem37.cs

@@ -29,7 +29,7 @@ namespace ProjectEulerCS.Problems{
 	public class Problem37 : Problem{
 		//Variables
 		//Static variables
-		private readonly long LAST_PRIME_BEFORE_CHECK = 7;
+		private static readonly long LAST_PRIME_BEFORE_CHECK = 7;
 		//Instance variables
 		private readonly List<long> truncPrimes;	//All numbers that are truncatable primes
 		private long sum;	//The sum of all elements in truncPrimes
@@ -141,7 +141,7 @@ namespace ProjectEulerCS.Problems{
 			//Throw a flag to show the problem is solved
 			solved = true;
 		}
-		//Reset the porblem so it can be run again
+		//Reset the problem so it can be run again
 		public override void Reset(){
 			base.Reset();
 			truncPrimes.Clear();

ProjectEulerCS/Problems/Problem38.cs

@@ -0,0 +1,115 @@
+//ProjectEuler/ProjectEulerCS/src/Problems/Problem38.cs
+//Matthew Ellison
+// Created: 10-11-21
+//Modified: 10-11-21
+//What is the largest 1-9 pandigital number that can be formed as the concatenated product of an integer with 1, 2, ... n where n > 1
+//Unless otherwise listed all non-standard includes are my own creation and available from https://bibucket.org/Mattrixwv/CSClasses
+/*
+	Copyright (C) 2021  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/>.
+*/
+
+
+namespace ProjectEulerCS.Problems{
+	public class Problem38 : Problem{
+		//Variables
+		//Static variables
+		private static readonly long HIGHEST_POSSIBLE_NUM = 9999;	//The highest number that needs to be checked for a 1-9 pandigital
+		//Instance variables
+		private long largestNum;	//The number passed to the executeFormula function that returns the largest pandigital
+		private long pandigital;	//The largest pandigital number found
+		//Gets
+		//The results of the problem
+		public override string Result{
+			get{
+				SolvedCheck("result");
+				return $"The largest appended product pandigital is {pandigital}";
+			}
+		}
+		public long LargestNum{
+			get{
+				SolvedCheck("largest number");
+				return largestNum;
+			}
+		}
+		public long Pandigital{
+			get{
+				SolvedCheck("pandigital");
+				return pandigital;
+			}
+		}
+		//Functions
+		//Constructor
+		public Problem38() : base("What is the largest 1-9 pandigital number that can be formed as the concatenated product of an integer with 1, 2, ... n where n > 1"){
+			largestNum = 0;
+			pandigital = 0;
+		}
+		//Operational functions
+		//Take the number and add its multiples to a string to return
+		private string ExecuteFormula(int num){
+			//Turn the current number into a string
+			string numStr = num.ToString();
+			int cnt = 2;
+			//Multiply the number and append the product to the string until you have one long enough
+			do{
+				numStr += (num * cnt).ToString();
+				++cnt;
+			}while(numStr.Length < 9);
+
+			return numStr;
+		}
+		//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();
+
+
+			//Loop from 1 -> HIGHEST_POSSIBLE_NUM checking for pandigitals
+			for(int cnt = 1;cnt <= HIGHEST_POSSIBLE_NUM;++cnt){
+				//Get the string from the formula
+				string numStr = ExecuteFormula(cnt);
+				long panNum = long.Parse(numStr);
+				//If the number is pandigital save it as the highest number
+				if(mee.StringAlgorithms.IsPandigital(numStr) && (panNum > pandigital)){
+					largestNum = cnt;
+					pandigital = panNum;
+				}
+			}
+
+
+			//Stop the timer
+			timer.Stop();
+
+			//Throw a flag to show the problem is solved
+			solved = true;
+		}
+		//Reset the problem so it can be run again
+		public override void Reset(){
+			base.Reset();
+			largestNum = 0;
+			pandigital = 0;
+		}
+	}
+}
+
+/* Results:
+The largest appended product pandigital is 932718654
+It took 4.055 milliseconds to solve this problem.
+*/