## LCC/Moose '20 Contest 4 S2 - Pens and Pencils

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Points: 5 (partial)
Time limit: 0.5s
Memory limit: 64M

Author:
Problem type

Chris has pencils in a line, some of which he wants to switch with pens. Chris has an unlimited supply of pens, but can only switch a single continuous segment pencils to pens at a time. Chris wants to end with a line of pencils and pens where there are exactly disjoint continuous segments of pens and he wants to do exactly operations of switching a segment of pencils into pens. Chris wants help on this problem, can you give him a set of segments to switch? He'll accept any valid solution!

#### Input Specification

The only line of input will consist of 3 space separated integers, (), (), ().

#### Output Specification

Output exactly lines of output, consisting of two space separated integers, and , indicating that Chris should switch () into pens. If this is impossible, output Impossible.

Note that none of the ranges can intersect.

#### Sample Input

10 3 3

#### Sample Output

4 6
1 2
9 9