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ProjectEulerJava/src/main/java/com/mattrixwv/project_euler/problems/Problem24.java
2023-06-30 21:59:11 -04:00

99 lines
2.9 KiB
Java

//ProjectEulerJava/src/main/java/mattrixwv/ProjectEuler/Problems/Problem24.java
//Matthew Ellison
// Created: 03-24-19
//Modified: 06-27-23
//What is the millionth lexicographic permutation of the digits 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9?
//Unless otherwise listed all non-standard includes are my own creation and available from https://bibucket.org/Mattrixwv/JavaClasses
/*
Copyright (C) 2023 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 com.mattrixwv.project_euler.problems;
import com.mattrixwv.StringAlgorithms;
import java.util.ArrayList;
import java.util.List;
public class Problem24 extends Problem{
//Variables
//Static variables
protected static int neededPerm = 1000000; //The number of the permutation that you need
protected static String nums = "0123456789"; //All of the characters that we need to get the permutations of
//Instance variables
protected List<String> permutations; //Holds all of the permutations of the string nums
//Functions
//Constructor
public Problem24(){
super(String.format("What is the %dth lexicographic permutation of the digits %s?", neededPerm, nums));
permutations = new ArrayList<>();
}
//Operational functions
//Solve the problems
@Override
public void solve(){
//If the problem has already been solved do nothing and end the function
if(solved){
return;
}
//Start the timer
timer.start();
//Get all the permutations of the string
permutations = StringAlgorithms.getPermutations(nums);
//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
@Override
public void reset(){
super.reset();
permutations.clear();
}
//Gets
//Returns the result of solving the problem
@Override
public String getResult(){
solvedCheck("result");
return String.format("The %dth permutation is %s", neededPerm, permutations.get(neededPerm - 1));
}
//Returns an ArrayList with all of the permutations
public List<String> getPermutationsList(){
solvedCheck("permutations");
return permutations;
}
//Returns the requested permutation
public String getPermutation(){
solvedCheck("1,000,000th permutation");
return permutations.get(neededPerm - 1);
}
}
/* Results
The 1 millionth permutation is 2783915460
It took an average of 1.140 seconds to run this problem through 100 iterations
*/