#!/usr/bin/perl
use warnings;
use strict;


my %out = map {
    my $name = "curve$_.out";
    open my $FH, '>', $name or die "cannot open $name $!";
    $_ => $FH;
    } 1, 2;

my $in ='curve12.data';
open my $IN, '<', $in or die "cannot open $in $!";

while ( <$IN> ) {
    if ( /^Curve(\d):/ .. /^\s*$/ ) {
        next unless /^\d/;
        exists $out{ $1 } and print { $out{ $1 } } "$_\n";
    }
}