ProjectEulerTS/Problems/Problem38.ts

//ProjectEulerTS/Problems/Problem38.ts
//Matthew Ellison
// Created: 11-11-21
//Modified: 11-11-21
//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/typescriptClasses
/*
	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/>.
*/


import { isPandigital } from "../../../Typescript/typescriptClasses/StringAlgorithms";
import { Problem } from "./Problem";


export class Problem38 extends Problem{
	//Variables
	//Static variables
	private static HIGHEST_POSSIBLE_NUMBER: number = 9999;	//The highest number that needs to be checked for a 1-9 pandigital
	//Instance variables
	private largestNum: number;	//The number passed to the executeFormula function that returns the largest pandigital
	private pandigital: number;	//The largest pandigital number found

	//Functions
	//Constructor
	public constructor(){
		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");
		this.largestNum = 0;
		this.pandigital = 0;
	}
	//Operational functions
	//Take the number and add its multiples to a string to return
	private executeFormula(num: number): string{
		//Turn the current number into a string
		let numStr = num.toString();
		let 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 problems
	public solve(): void{
		//If the problem has already been solved do nothing and end the function
		if(this.solved){
			return;
		}

		//Start the timer
		this.timer.start();


		//Loop from 1 -> HIGHEST_POSSIBLE_NUM checking for pandigitals
		for(let cnt = 1;cnt <= Problem38.HIGHEST_POSSIBLE_NUMBER;++cnt){
			//Get the string from the formula
			let numStr = this.executeFormula(cnt);
			let panNum = parseInt(numStr);
			//If the number is pandigital save it as the highest number
			if(isPandigital(numStr) && (panNum > this.pandigital)){
				this.largestNum = cnt;
				this.pandigital = panNum;
			}
		}


		//Stop the timer
		this.timer.stop();

		//Throw a flag to show the problem is solved
		this.solved = true;
	}
	//Reset the problem so it can be run again
	public reset(): void{
		super.reset();
		this.largestNum = 0;
		this.pandigital = 0;
	}

	//Gets
	//Returns a string with the solution tot he problem
	public getResult(): string{
		this.solvedCheck("results");
		return `The largest appended product pandigital is ${this.pandigital}`;
	}
	//Returns the largest number
	public getLargestNum(): number{
		this.solvedCheck("largest number");
		return this.largestNum;
	}
	//Returns the pandigital of the number
	public getPandigital(): number{
		this.solvedCheck("pandigital");
		return this.pandigital;
	}
}

/* Results:
The largest appended product pandigital is 932718654
It took an average of 3.051 milliseconds to run this problem through 100 iterations
*/