Create Prime_Numbers.go

Author: dynamitechetan

Prime_Numbers.go

@@ -0,0 +1,86 @@
+package main
+
+import (
+	"fmt"
+	"math"
+	"os"
+	"strconv"
+	"github.com/douglasmakey/golang-algorithms-/utils"
+	"time"
+)
+
+// Define struct
+type numberResult struct {
+	number  int64
+	isPrime bool
+}
+
+// Define functions
+
+// isPrime: validate N number is prime
+func isPrime(n int64) bool {
+	var i, limit int64
+	if n <= 1 {
+		return false
+	}
+
+	if n == 2 {
+		return true
+	}
+
+	if math.Mod(float64(n), 2) == 0 {
+		return false
+	}
+
+
+	limit = int64(math.Ceil(math.Sqrt(float64(n))))
+	for i = 3; i <= limit; i += 2 {
+		if math.Mod(float64(n), float64(i)) == 0 {
+			return false
+		}
+	}
+	return true
+}
+
+// createNrAndValidate: Receive number and validate if is prime, send channel this same
+func createNrAndValidate(n int64, c chan numberResult) {
+
+	result := new(numberResult)
+	result.number = n
+	result.isPrime = isPrime(n)
+	c <- *result
+}
+
+func initGoCalculations(min int64, max int64, c chan numberResult) {
+	var i int64
+	for i = min; i <= max; i++ {
+		go createNrAndValidate(i, c)
+	}
+}
+
+func primesInRange(min int64, max int64) (primeArr []int64) {
+	defer utils.TimeTrack(time.Now(), "primesInRange")
+
+	// Create channels and defer close
+	c := make(chan numberResult)
+	defer close(c)
+
+	// Execute N goroutines in range number
+	go initGoCalculations(min, max, c)
+
+	for i := min; i <= max; i++ {
+		// Receive numberResult
+		r := <-c
+		if r.isPrime {
+			primeArr = append(primeArr, r.number)
+		}
+	}
+	return
+}
+
+func main() {
+	// Receive arguments min max
+	min, _ := strconv.ParseInt(os.Args[1], 10, 64)
+	max, _ := strconv.ParseInt(os.Args[2], 10, 64)
+	fmt.Println(primesInRange(min, max))
+}