Data commit

Task/Pi/Wren/pi.wren

@@ -0,0 +1,39 @@
+import "/big" for BigInt
+import "io" for Stdout
+
+var calcPi = Fn.new {
+    var nn = BigInt.zero
+    var nr = BigInt.zero
+    var q  = BigInt.one
+    var r  = BigInt.zero
+    var t  = BigInt.one
+    var k  = BigInt.one
+    var n  = BigInt.three
+    var l  = BigInt.three
+    var first = true
+    while (true) {
+        if (q * BigInt.four + r - t < n * t) {
+            System.write(n)
+            if (first) {
+                System.write(".")
+                first = false
+            }
+            Stdout.flush()
+            nr = (r - n * t) * BigInt.ten
+            n = (q * BigInt.three + r) * BigInt.ten / t  - n * BigInt.ten
+            q =  q * BigInt.ten
+            r = nr
+        } else {
+            nr = (q * BigInt.two + r) * l
+            nn = (q * BigInt.new(7) * k + BigInt.two + r * l) / (t * l)
+            q  = q * k
+            t  = t * l
+            l  = l + BigInt.two
+            k  = k + BigInt.one
+            n = nn.copy()
+            r = nr
+        }
+    }
+}
+
+calcPi.call()