package main
import "fmt"
func main() {
   var binary int
   var octal int = 0
   j := 1
   var remainder int
   binary = 10011011
   binarynumber := binary
   for binary != 0 {
      remainder = binary % 10
      octal = octal + remainder*j
      j = j * 2
      binary = binary / 10
   }
   fmt.Println("The octal representation of binary number ", binarynumber, "is", octal)
   binary = 111111
   binarynumber = binary
   for binary != 0 {
      remainder = binary % 10
      octal = octal + remainder*j
      j = j * 2
      binary = binary / 10
   }
   fmt.Println("The octal representation of binary number ", binarynumber, "is", octal)
}

The octal representation of binary number  10011011 is 155
The octal representation of binary number  111111 is 16283

package main
import (
   "fmt"
   "math"
)

// initializing and defining a binary number to convert it into decimal
func toDecimal(number int) int {
   var remainder int
   value := 0
   decimalNumber := 0
   for number != 0 {
      remainder = number % 10
      number = number / 10
      decimalNumber = decimalNumber + remainder*int(math.Pow(2, float64(value)))
      value++
   }
   return decimalNumber
}
// initializing and defining a function to convert decimal to octal
func toOctal(number int) int {
   octal := 0
   counter := 1
   remainder := 0
   for number != 0 {
      remainder = number % 8
      number = number / 8
      octal += remainder * counter
      counter *= 10
   }
   return octal
}
func main() {
   number := 1001
   binarynum := number
   result := toDecimal(number)
   oct_num := toOctal(result)
   fmt.Println("The octal representation of binary number =", binarynum, "is: ", oct_num)
   number = 1100111
   binarynum = number
   result = toDecimal(number)
   oct_num = toOctal(result)
   fmt.Println("The octal representation of binary number =", binarynum, "is: ", oct_num)
}

The octal representation of binary number = 1001 is:  11
The octal representation of binary number = 1100111 is:  147