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dharanidharan
dharanidharan

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JavaScript Part-2

Operators

An operator is a symbol or keyword that tells JavaScript to perform a specific operation on one or more values (called operands).

For example, in the expression:

let sum = 10 + 5;//10 and 5 are operands.+ is the operator.The result is 15.

Types of Operators

JavaScript provides several types of operators:

1. Arithmetic Operators
Arithmetic operators perform mathematical calculations.

  • Addition 10 + 5
  • Subtraction 10 - 5
  • Multiplication 10 * 5 / Division 10 / 5 % Modulus (Remainder) 10 % 3 ** Exponentiation 2 ** 3

2. Assignment Operators
Assignment operators assign values to variables.

= x = 5 Assign
+= x += 2 Add and assign
-= x -= 2 Subtract and assign
*= x *= 2 Multiply and assign
/= x /= 2 Divide and assign

3. Comparison Operators

Comparison operators compare two values and return true or false.

== Equal to
!= Not equal

Greater than
< Less than
= Greater than or equal
<= Less than or equal

4. Logical Operators

Logical operators combine multiple conditions.

&& AND
|| OR
! NOT

5. Increment & Decrement Operators

These operators increase or decrease a value by 1.

Increment (++)

let count = 5;
count++;
console.log(count);

Output

6

Decrement (--)

let count = 5;
count--;
console.log(count);

Output

4

6. Ternary Operator

The ternary operator is a shorter way to write an if...else statement.

Syntax

condition ? value1 : value2;

Example

let age = 20;
let result = age >= 18 ? "Adult" : "Minor";
console.log(result);

Output
Adult

Reference:

JavaScript Operators-Geeksforgeeks

CONDITIONAL STATEMENTS

A conditional statement is used to execute different blocks of code depending on whether a condition is true or false.

Types of Conditional Statements

JavaScript provides the following conditional statements:

1. if Statement

The if statement executes a block of code only if the condition is true.

Syntax
if (condition) {
// Code to execute
}

Example

let age = 20;
if (age >= 18) {
console.log("You are eligible to vote.");
}

Output
You are eligible to vote.

2. if...else Statement

The if...else statement executes one block if the condition is true, otherwise it executes another block.

Syntax

if (condition) {
// Executes if true
} else {
// Executes if false
}

Example
let age = 16;
if (age >= 18) {
console.log("Eligible to vote");
} else {
console.log("Not eligible to vote");
}

Output
Not eligible to vote

3. if...else if...else Statement

Use this when you need to check multiple conditions.

Syntax

if (condition1) {

} else if (condition2) {

} else {

}

Example

let marks = 85;

if (marks >= 90) {
console.log("Grade A");
}
else if (marks >= 75) {
console.log("Grade B");
}
else if (marks >= 50) {
console.log("Grade C");
}
else {
console.log("Fail");
}

Output
Grade B

4. Nested if

A nested if means placing one if statement inside another.

Example

let age = 20;
let hasLicense = true;
if (age >= 18) {
if (hasLicense) {
console.log("You can drive.");
}
}

Output
You can drive.

5. switch Statement

The switch statement is used when you want to compare one value against many possible values.It is often cleaner than writing many else if statements.

Syntax

switch(expression){
case value1:
// Code
break;
case value2:
// Code
break;
default:
// Code
}

Example

let day = 3;
switch(day){
case 1:
console.log("Monday");
break;
case 2:
console.log("Tuesday");
break;
case 3:
console.log("Wednesday");
break;
default:
console.log("Invalid Day");
}

Output
Wednesday

Reference:

JavaScript Conditional Statements -Geeksforgeeks

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