These are few Javascript Ouput based interview question, which I faced during my interview process.

Question 1.

console.log('val1--val:',val1); 
val1 = 10;
test();
var val2 = 20;
const test = () => { console.log('hi')}
console.log('val2--val:',val2);
var val1;

Question 2.

let prom = new Promise((res, rej) => {
    console.log('synchronously executed');
    if (Math.random() > 0.5) {
        res('Success');
    } else {
        rej('Error');
    }
})
prom.then((val) => {
    console.log('asynchronously executed: ' + val); 
}).catch((err) => {
    console.log('asynchronously executed: ' + err); 
    console.log('promise done executing');
});
console.log('last log');

Question 3.

let person = {
    name: 'Anil Singh',
    age: 32
}

let members = [person];
person = null;
console.log(members); 
console.log(person);

Question 4.

let value = { members: 10 };
let multiply = ((x = { ...value }) => {
    console.log(x.members *= 2)
});

multiply();
multiply();
multiply(value);
multiply(value);

Question 5.

let a11 = {name:'a'};
let b11 = a11;
a11 = {age:30};

console.log(b11, a11);

Question 6.

let obj1 = {};
let obj2 = { a: 2 }
let obj3 = { b: 2 }

obj1[obj2] = 231;
obj1[obj3] = 333;

console.log(obj1[obj2])

Question 7.

console.log(11 + 11) 
console.log(011 + 011)
console.log(1 || 2 && 3)
console.log(1 && 2 || 3)
console.log(0.1 + 0.2 == 0.3)

Question 8.

console.log('1')
setTimeout(() => {
    console.log('Settimeout')
}, 0);
setInterval(() => {
    console.log('SetInterval')
}, 0);
console.log('2')

Question 9.

var valid = true;
setTimeout(() => {
    console.log('Settimeout');
    valid = false;
}, 100);

while(valid) {
    console.log('hi')
}

function output() {
    console.log(v);
    let v = 10;
}
output();

let user =  {
    fname:'singhak',
    getFname() {
    const fname = 'singhak.in';
    console.log(this.fname);
   }
}
user.getFname();