#! perl -slw
use strict;
use diagnostics;
use Data::Dump qw[ pp ];

my %in;
my %former_in;

while (<DATA>){
m[(\d\d):(\d\d) (.+)$] and push @{ $in{ $1 } }, $3 and $former_in{$3} = $2;
print STDOUT "1 is $1\n";
print STDOUT "2 is $2\n";
print STDOUT "3 is $3\n";
}

my @keys = keys %in;
my @times = sort @keys;

for my $hr ( sort{ $a <=> $b } keys %in ) {
    my $n = $#{ $in{ $hr } };
    my $step = 60 / $n;
    my $min = 0;
    for my $flight ( @{ $in{ $hr } } ) {
		my $former_time = $former_in{$flight};
		# relative difference
		my $diff = int( $min ) - $former_in{$flight};
        printf( "%02d:%02d %s %s\n", $hr, int( $min ), $flight, $diff );
        $min += $step;
        $min = 59 if $min > 59;
    }
}





__DATA__
11:10 A1
11:30 E4
11:30 Z4
11:50 H5
12:02 H6
12:25 B2
12:25 A8
12:30 F3
12:30 E7
12:50 E15
12:55 E16