JavaScript Coding Day 12 | JavaScript Operators: Arithmetic, Unary, and Assignment

JavaScript Operators: Arithmetic, Unary, and Assignment

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1. Arithmetic Operators

Arithmetic operators are used to perform mathematical calculations between variables or values. While most are familiar from basic math class, JavaScript includes a few powerful tools like Exponentiation (power) and Modulus (remainder).

• Addition (+): Adds numbers.

• Subtraction (-): Subtracts the right operand from the left.

• Multiplication (*): Multiplies two numbers.

• Exponentiation (**): Raises the first number to the power of the second (e.g., $6^2$).

• Division (/): Divides the left operand by the right.

• Modulus (%): Returns the remainder left over after division.

Practical Code Example

JavaScript

<script>
    var x = 6;
    var y = 2;

    console.log(x + y);  // Output: 8
    console.log(x - y);  // Output: 4
    console.log(x * y);  // Output: 12
    console.log(x ** y); // Output: 36 (6 to the power of 2)
    console.log(x / y);  // Output: 3
    console.log(x % y);  // Output: 0 (6 divides by 2 perfectly, no remainder)
</script>

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2. Unary Operators

Unary operators work on only one value (or operand). These are very popular in loops and counters.

• Pre-Increment (++a): Increases the value of the variable by 1 before using it.

• Pre-Decrement (--a): Decreases the value of the variable by 1 before using it.

Practical Code Example

JavaScript

<script>
    var a = 6;
    
    // a is currently 6. 
    // ++a adds 1 immediately, making it 7, then prints it.
    console.log(++a); // Output: 7

    // a is currently 7 (from the step above).
    // --a subtracts 1 immediately, making it 6, then prints it.
    console.log(--a); // Output: 6
</script>

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3. Assignment Operators

Assignment operators are used to assign values to variables. The basic one is =, but JavaScript offers "shorthand" operators that perform a math operation and save the result in one step.

• Addition Assignment (+=): Adds the value on the right to the variable on the left and saves the new result.

• Subtraction Assignment (-=): Subtracts the value on the right from the variable on the left and saves the new result.

Practical Code Example

JavaScript

<script>
    var c = 6;
    var d = 2;
    
    // Equivalent to: c = c + d
    // c becomes 6 + 2, which is 8
    console.log(c += d); // Output: 8
    
    // NOTE: c is now 8 (it changed in the line above)
    // Equivalent to: c = c - d
    // c becomes 8 - 2, which is 6
    console.log(c -= d); // Output: 6
</script>

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- by Chirana Nimnaka