The code is modified for your new requirement

use strict;
my %hash;while(<DATA>){ my($cord,@others)=split; 
push @{$hash{$cord}},\@others;} 
print map {my $__=$_;
 map {$__," @{$hash{$__}->[$_->[0]]}","\n"}
(sort {$a->[1] <=> $b->[1]} 
map{[$_,${$hash{$_}}->[$_]->[0]]} 0 .. $#{$hash{$__}})[0]}
sort {$a <=> $b}keys %hash
__DATA__
567         344     5   7     8 
1345        567     5   8     123
2346        78      12  1     567
3456        67      10  1     5
3456        789     10  3     6
4678        45      6   2     0
5349        6       8   2     14
6700        124     13  8     56
6700        50      13  1     4
8964        560     2   18    8
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