Pravin Varma

import React,{useMemo,useState} from “react”;import “./style.css”;export default function App() { const [state, setState] = useState(0); for(let i=1;i<10;i++){ let a=1; let b = 1; console.log(useMemo(()=> {console.log(‘invoked’);return a+b},[a,b]))

componentDidMount useEffect(() => { // will run on every render }); useEffect(() => { // will run on first render },[]); componentDidUpdate useEffect(() => {

This is the parent component import React,{useEffect, useState} from ‘react’; import ‘./style.css’; import Child1 from ‘./child1’; export default function App() { const [change, setChange] =

function Student() { this.obj = {}; this.setName = function(name) { this.obj.name = name; return this; }; this.setAge = function(age) { this.obj.age = age; return this;

The following code returns 1. It is tricky but should be eye opener. export default function App() { const [state, setState] = useState(”); useEffect(()=>{ console.log(1)