langs a-z

Task/Average-loop-length/Perl-6/average-loop-length.pl6

@@ -0,0 +1,18 @@
+constant MAX_N  = 20;
+constant TRIALS = 100;
+
+for 1 .. MAX_N -> $N {
+    my $empiric = TRIALS R/ [+] find-loop(random-mapping($N)).elems xx TRIALS;
+    my $theoric = [+]
+        map -> $k { $N ** ($k + 1) R/ [*] $k**2, $N - $k + 1 .. $N }, 1 .. $N;
+
+    FIRST say " N    empiric      theoric      (error)";
+    FIRST say "===  =========  ============  =========";
+
+    printf "%3d  %9.4f  %12.4f    (%4.2f%%)\n",
+            $N,  $empiric,
+                        $theoric, 100 * abs($theoric - $empiric) / $theoric;
+}
+
+sub random-mapping { hash .list Z=> .roll given ^$^size }
+sub find-loop { 0, %^mapping{*} ...^ { (state %){$_}++ } }

Task/Average-loop-length/Unicon/average-loop-length.unicon

@@ -0,0 +1,39 @@
+link printf, factors
+
+$define MAX_N 20
+$define TIMES 1000000
+$define RAND_MAX 2147483647
+
+procedure expected(n)
+    local sum := 0
+    every i := 1 to n do
+        sum +:= factorial(n) / (n ^ i) / factorial(n - i)
+    return sum
+end
+
+procedure test(n, times)
+    local i, count := 0, x, bits
+    every i := 0 to times-1 do {
+	x := 1
+	bits := 0
+	while iand(bits, x)=0 do {
+            count +:= 1
+            bits := ior(bits, x)
+            x := ishift(1 , ?n-1)
+        }
+    }
+    return count
+end
+
+procedure main(void)
+    local n, cnt, avg, theory, diff
+    write(" n\tavg\texp.\tdiff\n", repl("-",29))
+    every n := 1 to MAX_N do {
+        cnt := test(n, TIMES)
+        avg := real(cnt) / TIMES
+        theory := expected(n)
+        diff := (avg / theory - 1) * 100
+        printf("%2d %8.4r %8.4r %6.3r%%\n", n, avg, theory, diff)
+    }
+    return 0
+end