function Animal(name,age){
this.name = name
this.age = age
}
Animal.prototype.sayhi = function(){
console.log(`hello my name is ${this.name},age is ${this.age}`)
}
const sheep = new Animal('sheep')
sheep.sayhi()
function Cat(){
"use strict"
Animal.apply(this,arguments)
}
Cat.prototype = new Animal()
const amy = new Cat('roc',11)
amy.sayhi()