Permutation Matrix

[thornahawk]

I suppose there's been a shortage of challenges, 'ne? ;)

Anyway, here's a nice little challenge:

You are given a permutation matrix represented as a row index list. For instance:

[url="http://www.forkosh.dreamhost.com/mimetex.cgi?\left({\begin{array}0&1&0&0\\0&0&0&1\\0&0&1&0\\1&0&0&0\\\end{array}}\right)"]click to view image[/url]

would be represented as {2,4,3,1}.

The challenge is that, without using matrices, write a program that takes the row index list as input and outputs the column index list. For the example above, the output should be {4,1,3,2} .

thornahawk

[Weregoose]