Day 2 in JavaScript

JS Operators:

1. Arithmetic Operators: These operators are used to perform basic mathematical operation on numbers.

List of arithmetic operators:
a) Addition operator (+) :
Ex:

let x=10;
let y=5
let z=x+y; //15

If a string is added with a number, it will produce concatenation.
Concatenation:Joining two or more strings together.
Ex:

let x="10";
let y=5;
let z=x+y;

The value of z will be "105".

console.log(true+1); //2
This is a boolean condition[true=1, false=0]
Hence 1+1 = 2

b) Subtraction operator (-) :
Ex:

let x=10;
let y=5
let z=x-y; //5

In case of any string value [ex "10"] it will change the string value to integer and perform the subtraction.
parseInt(): It is a function in JS which is used to convert string to an integer.
Ex:

let x = "10";
let y = 5;
let z = parseInt(x) + y;

Output is 15.
If the string contains any name, it will try to change into integer. Or else it will return as NAN [not a number].

c) Multiplication operator (*) :
Ex:

let x=7;
let y=3;
let z=x*y; //21

d) Division operator (/) : It gives the quotient.
Ex:

let x=10;
let y=2
let z=x/y  //5

e) Modulus operator (%) : It gives the remainder.
Ex:

let x=10;
let y=2
let z=x%y //0

f) Exponential operator (**) :
Ex:

let x = 5;
let z = x ** 2; //25

g) Increment operator (++) :
This has 2 types: pre-increment and post-increment.
Post-increment:
Ex:

let i=10;
i=i+1; //11

It can also be written as

let i=10;
i++ ; //11

Pre-increment:
Ex:

let x = 5;
let y = ++x;
console.log (x); //6
console.log (y); //6

Pre-decrement:
Ex:

let j=10;
--j;
console.log(j); //9
console.log(--j); //8

Post-decrement:
Ex:

let x = 5;
let y = x--;
console.log(y); //5
console.log(x); //4

2) Comparison operators: These are used to compare two numbers and returns a boolean value.
List of comparison operators:
a) Equal to (==) : let 5==5 //true.
b) Equal value and equal type (===) : let "5"===5 // false.
c) Less than (<) : let 5<8 //true.
d) Less than or equal to (<=) : let 5<=5 //true.
e) Greater than (>) : let 8>5 //true.
f) Greater than or equal to (>=) : let 8>=5 //true.

Ex:

let i=5;
let j=7;
++i > --j // 6>6 which is false.

1. Logical operators: Multiple conditions can be combined using logical operators. They use logic to return true or false.

List of logical operators:
a) logical and (&&) - returns true only if both conditions are true.
Ex:

console.log(5 > 3 && 10 > 2); // true

b) logical or (||) - returns true if at least one condition is true and returns false only if both conditions are false.
Ex:

console.log(5 > 3 || 1 > 2); //true
console.log(1 > 5 || 2 > 4); //false

c) logical not (!) - The condition becomes reverse like true becomes false, false becomes true.