You need URL::Encode to decode the percent notation into octets, and Encode to turn the octets into unicode characters: 
#!/usr/bin/perl
use warnings;
use strict;
use feature qw{ say };

use open ':encoding(UTF-8)', ':std';

use Encode;
use URL::Encode qw{ url_decode };

my $string  = '%d0%be%d0%b1/%d1%81%d1%82%d0%b5%d0%bd';
my $octets  = url_decode($string);
my $unicode = decode('UTF-8', $octets);

say $unicode;

[download]

($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,

[download]

In reply to Re: To decode URL-decoded UTF-8 string. by choroba
in thread To decode URL-decoded UTF-8 string. by nikolay

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