javascript interview questions_1

 Q1:-

var a=2;

function display(){

    debugger;

    console.log('good morning');....callstack

}

display();

console.log(a);

Q2:-

var a=2;

console.log(show);.....memory?

debugger;

function display(){

   

    console.log('good morning');

}

var show=()=>{

    console.log('good night');

}

display();

console.log(a);

q3:

var a=2;

display();

showData();

console.log(a);

function display(){

 a=20;

    console.log(a);.....

}

function showData(){

    a=200;

    console.log(a);....

}

q4:

var a=2;

display();

showData();

console.log(a);......

function display(){

 var a=20;

    console.log(a);.....

}

function showData(){

   var a=200;

    console.log(a);.....

}

q5:

function a(){

    console.log(b);

}

var b=10;

a();

b=?

q6:

let a=10;

    var a=10;

error :--

    SyntaxError: Identifier 'a' has already been declared

q7:

const b=10;

b=2;

TypeError: Assignment to constant variable.

q8:-

 console.log(a);

    let a=10;

ReferenceError: Cannot access 'a' before initialization

q9:

var a=100;

{

//compound statement..

    var a=10;

    console.log( a);

}

console.log(a);

q10:

shadowing:--

let a=10;

{

   var a=100;

    console.log(a);

}

q11:

let b=100;

{

    var a=20;

    let b=30;

console.log(b);

}

console.log(b);