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-# Missing Reversed Inversions
-## Task 1: Missing Members
-> You are given two arrays of integers.
-> Write a script to find out the missing members in each other arrays.
-
-In set theory, given two sets A and B, this task asks for the difference sets A \ B and B \ A.
-
-There are many approches to solve this with Perl.
-The most basic way would be to use hashes as representations of sets.
-Hash slices come *very* handy when an array shall be convertet to as set:
-```
-my @a = (...);
-my %ha;
-@ha{@a} = ();
-```
-Now `%h` is a hash with all members of `@a` as keys.
-Taking the set difference A \ B to a second array `@b` is as easy as:
-```
-@b = (...);
-delete @ha{@b};
-```
-However, I prefer a more functional approach.
-Using PDL ndarrays of unique sorted numbers as set representations.
-Then we may use PDL set operation in a natural way to solve the task:
-```
-$m1 = long(...)->uniq;
-```
-makes `$m1` a 1-d ndarray representing a set and
-```
-setdiff_sorted($m1, $m2);
-```
-gives M1 \ M2.
-Same result, but better readable.
-## Task 2: Flip Matrix
-> You are given `n x n` binary matrix.
-> Write a script to flip the given matrix as below.
-
-Again, with PDL this task is almost trivial.
-Using `PDL::NiceSlice` we may reverse a dimension using the notation `(-1:0)`.
-Reverting a value is done with the unary negation operator `!`.
-Performing the "flip matrix" operation on a 2-d ndarray `$m` thus is as easy as:
-```
-!$m->(-1:0)
-``` \ No newline at end of file