#!/usr/bin/perl -w

use Modern::Perl;

my ($i, $j);

for ($i = 0; $i < 74; $i++)
{
    for ($j = 0; $j < 50; $j++)
    {
        my $r0 = $i;
        my $r1 = $i + 1;
        my $c0 = $j;
        my $c1 = ($j + 1) % 50;

        my $a = $r0 * 50 + $c0 + 1;
        my $b = $r0 * 50 + $c1 + 1;
        my $c = $r1 * 50 + $c1 + 1;
        my $d = $r1 * 50 + $c0 + 1;

        say "f $a/$a $b/$b $c/$c $d/$d";
    }
}