Added a pi estimation script

1 files changed, 36 insertions, 0 deletions

diff --git a/Perl/pi.pl b/Perl/pi.pl
new file mode 100644
index 0000000..263b312
--- /dev/null
+++ b/Perl/pi.pl
@@ -0,0 +1,36 @@
+#!/usr/bin/perl
+#!/data/data/com.termux/files/usr/bin/perl
+
+if (grep(/^$ARGV[0]$/, ('h', '-h', '--help'))) {
+    print "m.pl MAX_VALUE TOTAL_PAIRS\n";
+    exit;
+}
+
+($max_val, $total) = (shift // 120, shift // 500);
+
+print "PI estimate: " . est_pi($max_val, $total) . " with $total numbers between 0 and $max_val.\n";
+
+sub est_pi($$) {
+    my ($MAX_VAL, $TOTAL) = @_;
+    my $total_coprime;
+
+    foreach (1 .. $TOTAL) {
+        my $gcd = gcd_iter(rnd_int($MAX_VAL), rnd_int($MAX_VAL));
+
+        $total_coprime += ($gcd == 1);
+    }
+        
+    return sqrt(6/($total_coprime/$TOTAL));
+}
+
+sub rnd_int($) {
+    return int(rand(shift) + 0.5);
+}
+
+sub gcd_iter($$) {
+  my ($u, $v) = @_;
+  while ($v) {
+    ($u, $v) = ($v, $u % $v);
+  }
+  return abs($u);
+}