Data commit

Task/Additive-primes/Go/additive-primes.go

@@ -0,0 +1,60 @@
+package main
+
+import "fmt"
+
+func isPrime(n int) bool {
+    switch {
+    case n < 2:
+        return false
+    case n%2 == 0:
+        return n == 2
+    case n%3 == 0:
+        return n == 3
+    default:
+        d := 5
+        for d*d <= n {
+            if n%d == 0 {
+                return false
+            }
+            d += 2
+            if n%d == 0 {
+                return false
+            }
+            d += 4
+        }
+        return true
+    }
+}
+
+func sumDigits(n int) int {
+    sum := 0
+    for n > 0 {
+        sum += n % 10
+        n /= 10
+    }
+    return sum
+}
+
+func main() {
+    fmt.Println("Additive primes less than 500:")
+    i := 2
+    count := 0
+    for {
+        if isPrime(i) && isPrime(sumDigits(i)) {
+            count++
+            fmt.Printf("%3d  ", i)
+            if count%10 == 0 {
+                fmt.Println()
+            }
+        }
+        if i > 2 {
+            i += 2
+        } else {
+            i++
+        }
+        if i > 499 {
+            break
+        }
+    }
+    fmt.Printf("\n\n%d additive primes found.\n", count)
+}