@file = map { $$_[0] } 
        sort { $$a[1] <=> $$b[1] }
        map { [$_, (split /:/)[3] ] } @file;


##</code><code>##

@file = map { join ':', (split /:/)[1,2,3,0] }
        sort
        map { join ':', (split /:/)[3,0,1,2] } @file;