## Problem:

A permutation is an ordered arrangement of objects. For example, 3124 is one possible permutation of the digits 1, 2, 3 and 4. If all of the permutations are listed numerically or alphabetically, we call it lexicographic order. The lexicographic permutations of 0, 1 and 2 are:

012 021 102 120 201 210

What is the millionth lexicographic permutation of the digits 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9?

2783915460

## Code:The solution may include methods that will be found here: Library.java .

public interface EulerSolution{

public String run();

}
/*
* Solution to Project Euler problem 24
* By Nayuki Minase
*
* http://nayuki.eigenstate.org/page/project-euler-solutions
* https://github.com/nayuki/Project-Euler-solutions
*/

public final class p024 implements EulerSolution {

public static void main(String[] args) {
System.out.println(new p024().run());
}

public String run() {
// Initialize
int[] array = new int[10];
for (int i = 0; i < array.length; i++)
array[i] = i;

// Permute
for (int i = 0; i < 999999; i++) {
if (!Library.nextPermutation(array))
throw new AssertionError();
}

// Format output
String ans = "";
for (int i = 0; i < array.length; i++)
ans += array[i];
return ans;
}

}