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This is a program that I wrote a few years ago in order to test a theory that I read online. I read on some website that you could calculate the value of pi by throwing hot dogs on the floor which absolutely blew me away. I couldn't believe it, so I decided to test it. I wrote a program to simulate throwing 1 billion hot dogs on the floor and by golly let me tell you, they're right. Here's how: (Technically this works with any stick-like object.) Let x be the length of our object (hot dog in our case). You must then draw lines on the floor perpendicular to the direction you're facing which are all x length apart. This elegantly drawn image demonstrates what I mean flawlessly: The number of hot dogs which landed on a line divided by the total number of hot dogs thrown is an approximation for pi. Like I said, I simply refused to believe that something so simple could be possible so I wrote a program to simulate the process: #!/usr/bin/perl -w use strict; my($dist, $lower, $upper, $lenComponent, $approx); my $len = 6; my $throws = 1000000; #CHANGE TO WHAT YOU WANT my $intersects = 0; for(1..$throws){ $dist = rand(180); #arbitrary maximum throwing distance $lenComponent = sin(rand(6.28318530718))*$len; #trig with up to 2pi radians rotation $lower = $dist - ($lenComponent/2); $upper = $lower + $lenComponent; for(my $line = 0; $line<=($dist+$len); $line+=$len){ if($line>=$lower and $line<=$upper){ ++$intersects; last; } } } $approx = (1/$intersects)*$throws; print "Pi is approximately: $approx"; And I ran the program overnight with 1 BILLION hot dogs, which yielded this result: 3.14154932843791 VS 3.14159265358979 Error: 0.00004332515 Wowza! I also wrote a second version of the program which uses multi-threading to throw the hot dogs faster. It was actually a neat exercise because I wrote it such that all of the threads can edit the same variable which counts the total number of intersections. Code: #!usr/bin/perl -w use strict; use threads; use threads::shared; my $intersects :shared = 0; my $throws = 10000000; my @threads = (); sub hotdog{ my($dist, $lenComponent, $lower, $upper); my $len = 1; for(1..$throws){ $dist = rand(5); #arbitrary maximum throwing distance $lenComponent = sin(rand(6.28318530718))*$len; #trig with up to 2pi radians rotation $lower = $dist - ($lenComponent/2); $upper = $dist + ($lenComponent/2); for(my $line = 0; $line<=($dist+$len); $line+=$len){ if($line>=$lower and $line<=$upper){ lock($intersects); ++$intersects; last; } } } } for(1..10){ push (@threads, threads->create(\&hotdog)); } $_->join foreach @threads; print "Pi is approximately: ".(($throws*scalar(@threads))/$intersects);