in reply to Re: Better way of writing "find the missing number(s)"
in thread Better way of writing "find the missing number(s)"

ah! given the above task the oneliner is much simpler!

perl -E "@ar=(1..3,5,6,7);$h{$_}++for$ar[0]..$ar[-1];delete$h{$_}for@a +r;print keys %h" 4

L*

There are no rules, there are no thumbs..
Reinvent the wheel, then learn The Wheel; may be one day you reinvent one of THE WHEELS.

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Re^3: Better way of writing "find the missing number(s)" -- oneliner
by tybalt89 (Monsignor) on Apr 04, 2017 at 07:50 UTC

    Slices, slices...

    perl -E '\@h{1..(@a=(1..3,5,6,7))+1};delete@h{@a};say%h'
Re^3: Better way of writing "find the missing number" -- oneliner
by salva (Canon) on Apr 04, 2017 at 07:50 UTC
    hey, let's play golf!
    perl -e'$_>++$i&&die"$i\n"for 1..3,5,6,7'
Re^3: Better way of writing "find the missing number" -- oneliner
by tybalt89 (Monsignor) on Apr 04, 2017 at 08:44 UTC

    Or an array version.

    perl -E '@b=0..(@a=(1..3,5,6,7))+1;@b[0,@a]="";say@b'