feat(generatePrimes): number of routines now dependent on number of CPUs

main.go

@@ -7,6 +7,7 @@ import (
 	"fmt"
 	"log"
 	"os"
+	"runtime"
 	"strconv"
 	"time"
 )
@@ -52,12 +53,18 @@ func checkIsDivisibleByPrime(number, offset, stride int, primes *[]int, resultCh
 func generatePrimes(upperLimit int, loadList bool) []int {
 	var primes []int
 
+	bootTime := time.Now()
+
 	if loadList {
 		primes = loadPrimes()
 	} else {
 		primes = []int{2, 3, 5}
 	}
 
+	numRoutines := runtime.NumCPU()
+
+	fmt.Printf("Startup time: %v\nCalculating with %d routines\n\n", time.Now().Sub(bootTime), numRoutines)
+
 	progress := make(chan float32)
 	go printProgress(progress, "Generating primes")
 
@@ -73,7 +80,6 @@ func generatePrimes(upperLimit int, loadList bool) []int {
 
 		checkCtx, checkCancel := context.WithCancel(context.Background())
 		resultChannel := make(chan bool)
-		numRoutines := 12
 
 		for r := 0; r < numRoutines; r++ {
 			go checkIsDivisibleByPrime(i, r, numRoutines, &primes, resultChannel, checkCtx)