Parallel fib In Go

package main
import(
 "fmt"
 "time"
 "runtime"
)


func fib(n uint64) uint64 {
 if n <= 2 {
  return 1
 }
 return fib(n-1) + fib(n-2)
}

func pfib(n uint64) uint64 {
 if n <= 2 { // terminate recursion
  return 1
 }
 // create a channel for subtask results
 res := make(chan uint64, 2)
 // fork 2 subtasks, they will send results to the res channel
 go func() {
  res <- fib(n - 1)
 }()
 go func() {
  res <- fib(n - 2)
 }()
 return <-res + <-res
}



func main(){
 
 runtime.GOMAXPROCS(2)
 t0 := time.Now()
 fmt.Printf(" %d\n", pfib(48) )
 t1 := time.Now()
    fmt.Printf("time %v to run.\n", t1.Sub(t0))
 
 
}