Write a Golang program to find prime numbers in a given range

Examples

• Input num1=3 and num2=8 => Prime numbers are: 3, 5, 7
• Input num1=8 and num2=23 => Prime numbers are: 11, 13, 17, 19, 23

Approach to solve this problem

• Step 1: Define a function that accepts two numbers, num1 and num2, type is int.
• Step 2: Iterate between num1 and num2.
• Step 3: If the number is prime, then print that number, else break.

Program

Live Demo

package main
import (
   "fmt"
   "math"
)

func printPrimeNumbers(num1, num2 int){
   if num1<2 || num2<2{
      fmt.Println("Numbers must be greater than 2.")
      return
   }
   for num1 <= num2 {
      isPrime := true
      for i:=2; i<=int(math.Sqrt(float64(num1))); i++{
         if num1 % i == 0{
            isPrime = false
            break
         }
      }
      if isPrime {
         fmt.Printf("%d ", num1)
      }
      num1++
   }
   fmt.Println()
}

func main(){
   printPrimeNumbers(5, 19)
   printPrimeNumbers(0, 2)
   printPrimeNumbers(13, 100)
}

Output

5 7 11 13 17 19
Numbers must be greater than 2.
13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83 89 97