Data commit

Task/Cuban-primes/Go/cuban-primes.go

@@ -0,0 +1,46 @@
+package main
+
+import (
+    "fmt"
+    "math/big"
+)
+
+func commatize(n uint64) string {
+    s := fmt.Sprintf("%d", n)
+    le := len(s)
+    for i := le - 3; i >= 1; i -= 3 {
+        s = s[0:i] + "," + s[i:]
+    }
+    return s
+}
+
+func main() {
+    var z big.Int
+    var cube1, cube2, cube100k, diff uint64
+    cubans := make([]string, 200)
+    cube1 = 1
+    count := 0
+    for i := 1; ; i++ {
+        j := i + 1
+        cube2 = uint64(j * j * j)
+        diff = cube2 - cube1
+        z.SetUint64(diff)
+        if z.ProbablyPrime(0) { // 100% accurate for z < 2 ^ 64
+            if count < 200 {
+                cubans[count] = commatize(diff)
+            }
+            count++
+            if count == 100000 {
+                cube100k = diff
+                break
+            }
+        }
+        cube1 = cube2
+    }
+    fmt.Println("The first 200 cuban primes are:-")
+    for i := 0; i < 20; i++ {
+        j := i * 10
+        fmt.Printf("%9s\n", cubans[j : j+10]) // 10 per line say
+    }
+    fmt.Println("\nThe 100,000th cuban prime is", commatize(cube100k))
+}