// use reduce function to find sum of all elements in array
const array = [1,2,3,4,5];
const sumValue = array.reduce((sum, value)=> sum + value, 0); // 15

// check all the children is valid or not.
root.children.every(child => !child)


// filtering the values in JSON.stringify.

const person = {
  name: "Ajaykumar",
  company: "eBay"
}
const output = JSON.stringify(person, (key,value) => {
  if(key === "company") return undefined;
  return value;
});
console.log(output) // {"name":"Ajaykumar"} 

// check if its mac browser 
const isMac = /Mac|iPod|iPhone|iPad/.test(navigator.platform);