« Blog » 2009-07-30

Permutations

Created 2009-07-30T03:56:12.755Z, last edited 2009-07-30T04:02:52.837Z

Something simple today I think. This is another puzzle stolen from Project Euler.

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?

There is a very simple trick to this one.