Decimal to roman numeral converter in golang

Go program for Decimal to roman numeral converter. Here more solutions.

package main
import "fmt"

//  Golang program for
//  Conversion from Decimal to roman number

// Display roman value of n
func result(n  int64) {
    switch (n) {
    // Test Cases
    case 1:
        fmt.Print("I");
        break;
    case 4:
        fmt.Print("IV");
        break;
    case 5:
        fmt.Print("V");
        break;
    case 9:
        fmt.Print("IX");
        break;
    case 10:
        fmt.Print("X");
        break;
    case 40:
        fmt.Print("XL");
        break;
    case 50:
        fmt.Print("L");
        break;
    case 90:
        fmt.Print("XC");
        break;
    case 100:
        fmt.Print("C");
        break;
    case 400:
        fmt.Print("CD");
        break;
    case 500:
        fmt.Print("D");
        break;
    case 900:
        fmt.Print("DM");
        break;
    case 1000:
        fmt.Print("M");
        break;
    }
}
func selecting(number int64, collection []int64,  size  int64)int64 {
    var  n  int64 = 1;
    var  i  int64 = 0;
    for i = 0; i < size; i++ {
        if (number >= collection[i]) {
            n = collection[i];
        } else {
            break;
        }
    }
    result(n);
    // Reduce the value of number
    return number - n;
}
func romanNo(number  int64) {
    if (number <= 0) {
        // When is not a natural number
        return;
    }
    // Base case collection
    var  collection = []int64 {1, 4, 5, 9, 10, 40, 50, 90, 100, 400, 500, 900, 1000}
    // Get the size of collection
    var  size  int64 = int64(len(collection));
    fmt.Printf(" %d : ",number);
    for(number > 0) {
        number = selecting(number, collection, size);
    }
    // Add new line
    fmt.Println();
}

func main() {
    // Test Case
    romanNo(10);
    romanNo(18);
    romanNo(189);
    romanNo(604);
    romanNo(982);
    romanNo(3000);
 }

Output

 10 : X
 18 : XVIII
 189 : CLXXXIX
 604 : DCIV
 982 : DMLXXXII
 3000 : MMM