Added solution to problem 38

src/main/java/mattrixwv/ProjectEuler/ProblemSelection.java

@@ -36,7 +36,7 @@ public class ProblemSelection{
 	public static final ArrayList<Integer> PROBLEM_NUMBERS = new ArrayList<Integer>(Arrays.asList( 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));
+																									  31, 32, 33, 34, 35, 36, 37, 38, 67));
 
 	//Returns the problem corresponding to the given problem number
 	public static Problem getProblem(Integer problemNumber){
@@ -79,6 +79,7 @@ public class ProblemSelection{
 			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;

src/main/java/mattrixwv/ProjectEuler/Problems/Problem37.java

@@ -121,7 +121,7 @@ public class Problem37 extends Problem{
 		//Stop the timer
 		timer.stop();
 
-		//Throw a flag to show the porblem is solved
+		//Throw a flag to show the problem is solved
 		solved = true;
 	}
 	//Reset the problem so it can be run again

src/main/java/mattrixwv/ProjectEuler/Problems/Problem38.java

@@ -0,0 +1,116 @@
+//ProjectEulerJava/src/main/java/mattrixwv/ProjectEuler/Problems/Problem37.java
+//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/JavaClasses
+/*
+	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/>.
+*/
+package mattrixwv.ProjectEuler.Problems;
+
+
+import mattrixwv.StringAlgorithms;
+
+
+public class Problem38 extends Problem{
+	//Variables
+	//Static variables
+	private static final 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
+
+	//Functions
+	//Constructor
+	public Problem38(){
+		super("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 = Integer.toString(num);
+		int cnt = 2;
+		//Multiply the number and append the product to the string until you have one long enough
+		do{
+			numStr += Integer.toString(num * cnt);
+			++cnt;
+		}while(numStr.length() < 9);
+
+		return numStr;
+	}
+	//Solve the problem
+	public 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.parseLong(numStr);
+			//If the number is pandigital save it as the highest number
+			if(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 prblem so it can be run again
+	public void reset(){
+		super.reset();
+		largestNum = 0;
+		pandigital = 0;
+	}
+
+	//Gets
+	//Returns a string with the solution to the problem
+	public String getResult(){
+		solvedCheck("results");
+		return String.format("The largest appended product pandigital is %d", pandigital);
+	}
+	//Returns the largest number
+	public long getLargestNum(){
+		solvedCheck("largest number");
+		return largestNum;
+	}
+	//Returns the pandigital of the number
+	public long getPandigital(){
+		solvedCheck("pandigital");
+		return pandigital;
+	}
+}
+
+/* Results:
+The largest appended product pandigital is 932718654
+It took 16.947 milliseconds to solve this problem.
+*/