package main

import "fmt"

type cat struct {
	name string
	age  int
}

func (n *cat) add() {
	n.age = n.age + 1
}

func (n cat) show() {
	fmt.Println(n)
}

func main() {
	newCat := cat{name: "kitty", age: 3}
	newCat.show()
	newCat.add()
	newCat.show()
}