golang递归函数如何检查返回值？

Learning golang, proect euler problem 5. I was messing around with a recursive function and I could not figure out a way to get the return value to be correct.

In go I cannot take out the return at the end of the five() function and I also cannot get it to return the right value to execute the if statement in the main() function...

I realize I can do this without the recursion but I would like to know how to do it with recursion if possible.

package main

import (
    "fmt"
    //"os"
)

func recursive(num int, div int) int {

    if div == 1 {
        fmt.Println(num)
        return num
    }
    switch num % div {
    case 0:
        recursive(num, div-1)
    default:
        return -1
    }
    return num
}

func main() {
    for i := 20; ; i += 20 {
        if recursive(i, 19) == 1 {
            fmt.Println("finished")
        }
    }
}

Oh, and besides the comments above, it should also break once the answer is found.

package main

import (
    "fmt"
    //"os" 
)

func recursive(num int, div int) int {
    if div == 1 {
         return 1
    }
    switch num % div {
    case 0:
        return recursive(num, div-1)
    default:
        return -1
    }
    return num
 }

 func main() {
    for i := 120; ; i += 20 {
        if recursive(i, 19) == 1 {
            fmt.Printf ("finished with %v
", i)
            break;
        }
    }
 }