#!/usr/bin/perl -w

use constant HIGH => 10_000;
my $ans = int(rand(HIGH)) + 1;
my ( $lower, $higher ) = (1, HIGH);
while(1) {
    my $guess = int(($lower + $higher)/2);
    print "Guessing: $guess\n";
  last if $ans == $guess;
    if ( $guess > $ans ) {
        print "Lower...";
        $higher = $guess -1;
    }
    else {
        print "Higher...";
        $lower = $guess +1;
    }
}
print "The guess was correct!";