2020_who_is_faster_golang.sh

package main

import (
   "fmt"
   "math"
   "time"
)

func isPrime(num int) bool {
   if num == 2 {
      return true
   }
   if num == 1 || num%2 == 0 {
      return false
   }
   to := int(math.Sqrt(float64(num)))
   for div := 3; div <= to; div += 2 {
      if num%div == 0 {
         return false
      }
   }
   return true
}

func do(N int) {
   for i := 0; i < N; i++ {
      prime := isPrime(i)
      if prime {
         // fmt.Printf("%+v: %+v\n", i, prime)
      }
   }
}

func main() {
   st := time.Now()
   do(10_000_000)
   fmt.Printf("%+v\n", time.Since(st))
}