Added solution to problem 32

This commit is contained in:
2020-10-03 12:51:29 -04:00
parent e2be18dbaf
commit bb61cda17e
2 changed files with 175 additions and 1 deletions

View File

@@ -33,7 +33,7 @@ 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, 67};
30, 31, 32, 67};
public static System.Collections.Generic.List<int> PROBLEM_NUMBERS{
get { return _PROBLEM_NUMBERS; }
}
@@ -73,6 +73,7 @@ namespace ProjectEulerCS{
case 29: problem = new Problem29(); break;
case 30: problem = new Problem30(); break;
case 31: problem = new Problem31(); break;
case 32: problem = new Problem32(); break;
case 67: problem = new Problem67(); break;
}
return problem;

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@@ -0,0 +1,173 @@
//ProjectEuler/ProjectEulerCS/src/Problems/Problem32.cs
//Matthew Ellison
// Created: 10-03-20
//Modified: 10-03-20
//Find the sum of all products whose multiplicand/multiplier/product identity can be written as a 1 through 9 pandigital.
//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.Collections.Generic;
namespace ProjectEulerCS.Problems{
public class Problem32 : Problem{
//Structures
//Holds the set of numbers that make a product
private struct ProductSet{
private readonly int multiplicand;
private readonly int multiplier;
public int Multiplicand{
get{
return multiplicand;
}
}
public int Multiplier{
get{
return multiplier;
}
}
public int Product{
get{
return (multiplicand * multiplier);
}
}
public ProductSet(int multiplicand, int multiplier){
this.multiplicand = multiplicand;
this.multiplier = multiplier;
}
public override bool Equals(object obj){
if(obj == null || GetType() != obj.GetType()){
return false;
}
ProductSet secondSet = (ProductSet)obj;
//Return true if the products are the same
return (Product == secondSet.Product);
}
public override int GetHashCode(){
return multiplicand ^ multiplier;
}
public override string ToString(){
return $"{multiplicand}{multiplier}{Product}";
}
}
//Variables
//Static variables
private const int TOP_MULTIPLICAND = 99; //The largest multiplicand to check
private const int TOP_MULTIPLIER = 4999; //The largest multiplier to check
//Instance variables
private readonly List<ProductSet> listOfProducts; //The list of unique products that are 1-9 pandigital
private long sumOfPandigitals; //THe sum of the products of the pandigital numbers
//Gets
public long SumOfPandigitals{
get{
if(!solved){
throw new Unsolved();
}
return sumOfPandigitals;
}
}
public override string Result{
get{
if(!solved){
throw new Unsolved();
}
return $"There are {listOfProducts.Count} unique 1-9 pandigitals\nThe sum of the products of these pandigitals is {sumOfPandigitals}";
}
}
//Functions
//Constructor
public Problem32() : base("Find the sum of all products whose multiplicand/multiplier/product identity can be written as a 1 through 9 pandigital."){
listOfProducts = new List<ProductSet>();
sumOfPandigitals = 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();
//Create the multiplicand and start working your way up
for(int multiplicand = 1;multiplicand <= TOP_MULTIPLICAND;++multiplicand){
//Run through all possible multipliers
for(int multiplier = multiplicand;multiplier <= TOP_MULTIPLIER;++multiplier){
ProductSet currentProductSet = new ProductSet(multiplicand, multiplier);
//If the product is too long move on the the next possible number
if(currentProductSet.ToString().Length > 9){
break;
}
//If the current number is pandigital that doesn't already exist in the list add it to the list
if(IsPandigital(currentProductSet)){
if(!listOfProducts.Contains(currentProductSet)){
listOfProducts.Add(currentProductSet);
}
}
}
}
//Get the sum of the products of the pandigitals
foreach(ProductSet prod in listOfProducts){
sumOfPandigitals += prod.Product;
}
//Stop the timer
timer.Stop();
//Throw a flag to show the problem is solved
solved = true;
}
//Returns true if the passed productset is 1-9 pandigital
private bool IsPandigital(ProductSet currentSet){
//Get the numbers out of the object and put them into a string
string numberString = currentSet.ToString();
//Make sure the string is the correct length
if(numberString.Length != 9){
return false;
}
//Make sure every number from 1-9 is contained exactly once
for(int panNumber = 1;panNumber <= 9;++panNumber){
//Make sure there is exactly one of this number contained in the string
if(mee.Algorithms.FindNumOccurrence(numberString, panNumber.ToString()[0]) != 1){
return false;
}
}
//If all numbers were found in the string return true
return true;
}
//Reset the problem so it can be run again
public override void Reset(){
base.Reset();
listOfProducts.Clear();
sumOfPandigitals = 0;
}
}
}
/* Results:
There are 7 unique 1-9 pandigitals
The sum of the products of these pandigitals is 45228
It took an average of 16.960 milliseconds to run this problem through 100 iterations
*/