Find the frequency of each element in an array in golang

Go program for Find the frequency of each element in an array. Here more information.

package main
import "fmt"
/*
  Go program
  Count frequency of each element in array 
*/

// Function which is display array elements
func display(arr[] int) {
	for i := 0 ; i < len(arr) ; i++ {
		fmt.Print("   ", arr[i])
	}
	fmt.Print("\n")
}
// Count occurrence of given array
func frequency(arr[] int) {
	// Display given array
	display(arr)
	// Create a empty map
	var m = make(map[int] int)
	for i := 0 ; i < len(arr) ; i++ {
		if _, found := m[arr[i]] ; found {
			// When key exists then update value
			m[arr[i]] = m[arr[i]] + 1
		} else {
			// Add new element
			m[arr[i]] = 1
		}
	}
	fmt.Println("  Occurrence ")
	//  Display calculated result
	for k, v := range m {
		fmt.Println("  ", k, "  :  ", v)
	}
}
func main() {
	// Array element
	var arr = [] int {
		1,
		3,
		2,
		1,
		4,
		2,
		7,
		9,
		1,
		3,
		3,
		4,
		7,
	}
	frequency(arr)
}

Output

  1  3  2  1  4  2  7  9  1  3  3  4  7
  Occurrence
  1  :  3
  2  :  2
  3  :  3
  4  :  2
  7  :  2
  9  :  1