Data commit

Task/Arithmetic-Rational/Go/arithmetic-rational.go

@@ -0,0 +1,32 @@
+package main
+
+import (
+    "fmt"
+    "math"
+    "math/big"
+)
+
+func main() {
+    var recip big.Rat
+    max := int64(1 << 19)
+    for candidate := int64(2); candidate < max; candidate++ {
+        sum := big.NewRat(1, candidate)
+        max2 := int64(math.Sqrt(float64(candidate)))
+        for factor := int64(2); factor <= max2; factor++ {
+            if candidate%factor == 0 {
+                sum.Add(sum, recip.SetFrac64(1, factor))
+                if f2 := candidate / factor; f2 != factor {
+                    sum.Add(sum, recip.SetFrac64(1, f2))
+                }
+            }
+        }
+        if sum.Denom().Int64() == 1 {
+            perfectstring := ""
+            if sum.Num().Int64() == 1 {
+                perfectstring = "perfect!"
+            }
+            fmt.Printf("Sum of recipr. factors of %d = %d exactly %s\n",
+                candidate, sum.Num().Int64(), perfectstring)
+        }
+    }
+}