Data commit

Task/Arithmetic-derivative/Go/arithmetic-derivative.go

@@ -0,0 +1,46 @@
+package main
+
+import (
+    "fmt"
+    "rcu"
+)
+
+func D(n float64) float64 {
+    if n < 0 {
+        return -D(-n)
+    }
+    if n < 2 {
+        return 0
+    }
+    var f []int
+    if n < 1e19 {
+        f = rcu.PrimeFactors(int(n))
+    } else {
+        g := int(n / 100)
+        f = rcu.PrimeFactors(g)
+        f = append(f, []int{2, 2, 5, 5}...)
+    }
+    c := len(f)
+    if c == 1 {
+        return 1
+    }
+    if c == 2 {
+        return float64(f[0] + f[1])
+    }
+    d := n / float64(f[0])
+    return D(d)*float64(f[0]) + d
+}
+
+func main() {
+    ad := make([]int, 200)
+    for n := -99; n < 101; n++ {
+        ad[n+99] = int(D(float64(n)))
+    }
+    rcu.PrintTable(ad, 10, 4, false)
+    fmt.Println()
+    pow := 1.0
+    for m := 1; m < 21; m++ {
+        pow *= 10
+        fmt.Printf("D(10^%-2d) / 7 = %.0f\n", m, D(pow)/7)
+    }
+}