function a(){
  console.log(b) // output: ƒ b(){ console.log("hi") }
  var b = 10;
  return
  function b(){ console.log("hi") }
}
a()

var a = 10;
function b() {
  a = 1;
  return;
  function a(){};
}
b();
console.log(a) // output: 10

function sayHi() {
    console.log(name); // output: undefined
    console.log(age); // reference error
    var name = 'sunil';
    let age = 21;
}
sayHi()

console.log(a) // output: undefined
var a = "test"
sayHello() // error
a()
var a = function sayHello(){ console.log("hi") }

var x = 10
function y(){
  x = 100
  return 
}
y()
console.log(x) // output: 100

var x = 10
function y(){
  x = 100
  return 
  var x = function(){ console.log("hi") }
}
y()
console.log(x) // output: 10

var x = 10
function y(){
  x = 100
  return 
  x = function(){ console.log("hi") }
}
y()
console.log(x) // output: 100

console.log(a())
function a(){
  console.log("gg")
}

console.log(b())
var b = function(){
  console.log("gg")
}

console.log(c(), d())
var c = function d(){
  console.log("gg")
}

var a = {key: 1};
var b = {key: 1};
console.log(a == b); // false    
console.log(a === b); // false   

console.log(null == null); // true 
console.log(null === null); // true 
console.log(undefined == undefined); // true 
console.log(undefined === undefined); // true
console.log(NaN == NaN); //false
console.log(NaN === NaN); //false

const x = {
  firstName: '',
  lastName: '',
  setName: function(name) {
    console.log(this)
    let splitName = function(n) {
      console.log(this)
      const nameArr = name.split(' ');
      this.firstName = name[0];
      this.lastName = name[1];
    }
    splitName(name);
  }
}
var name = 'Jon doe';
x.setName(name);
console.log(x.firstName); // undefined
console.log(x.lastName); // undefined

var Foo = function( a ) {
  function bar() {   
    return a; 
  }
  
  this.baz = function() {
    return a; 
  };
};

Foo.prototype = {
  biz: function() {    
    return a; 
  }
};

var f = new Foo( 7 );
f.bar(); // error bar is not fn
f.baz(); // 7
f.biz(); // undefined

// Modify the above declaration so that the output is 7 for each of the declared functions

function a(){
  console.log(this)
}
a() // window


var a = function(){
  console.log(this)
}
a() // window


var a = function sayHello(){
  console.log(this)
}
a() // window

obj = {
  name: "supername",
  getN: function(){
    console.log(this.name) // supername, this = obj
    function x(){
      console.log(this.name) // undefined, this = window
    }
    x()
  }
}
obj.getN()
// How to fix above so that inside function x, this refers to obj
// Hint: Fat arrow, Bind, Call

console.log("A")
setTimeout(function(){ console.log("B") }, 1000)
console.log("C")
// output:
// A
// C
// B (after atleast 1 sec)

console.log("A")
setTimeout(function(){ console.log("B") }, 0)
console.log( console.log("C") )
// output:
// A
// C
// B (immediately after C is printer)

setTimeout(function(){ console.log("2000") }, 2000)
setTimeout(function(){ console.log("1000") }, 1000)
setTimeout(function(){ console.log("4000") }, 4000)

Create a function sum which when called sum(1,2,3....n)() or sum(1)(2)(3)...(n)() should yield same result.

For a given n number of arguments, create a function sum which when called

• sum(1,2,3....n)
• sum(1)(2)(3)...(n)
• sum(1,2,3)(4,5,...n)
• sum(1,2)(3,4)(5)(6,7)..(n)
• sum(1,2,3...n-2)(n-1, n) all should yield the same result.

Create a function such that sentence("I")("am")("going")("out.") should output I am going out. The last parameter will always contain full stop.

• sentence("I")("am")("going")("out.")
• sentence("I am")("going")("out.")
• sentence("I am going")("out.")
• sentence("I")("am going out.") all should yield same result I am going out.

for(var i = 0 ; i < 10; i++) {
    setTimeout(function(){
        console.log(i)
    }, 1000)
}

What will be the output? What are the various ways so that proper value for i is printed? (Hint: let, iife)

function createButtons(){
  for (var i = 1; i <= 5; ++i) {
    var body = document.getElementsByTagName("body")
    var button = document.createElement("button")
    button.innerHTML = 'button' + i
    button.onclick = function(){
      console.log('this is button' + i)
    }
    body.appendChild(button)
  }
}

How can you fix the issue if any?