Control Structures

Control Structures in Programming

Iteration (Loops)

Loops allow us to repeat a block of code multiple times.

For Loop

for (let i = 0; i < 5; i++) {
    console.log("Iteration number: " + i);
}

While loop

for (let count = 0;
while (count < 5) {
    console.log("Count is: " + count);
    count++;
}) {
    console.log("Iteration number: " + i);
}

Do-While Loop

let num = 0;
do {
    console.log("Number: " + num);
    num++;
} while (num < 5);;

Conditional Statements

Conditionals control decision-making in a program based on Boolean conditions.

If statement

let age = 18;
if (age >= 18) {
    console.log("You are an adult.");
}

If Else Statement

let temperature = 30;
if (temperature > 25) {
    console.log("It’s hot outside.");
} else {
    console.log("It’s cool outside.");
}

Else If Ladder

let score = 85;
if (score >= 90) {
    console.log("Grade: A");
} else if (score >= 80) {
    console.log("Grade: B");
} else if (score >= 70) {
    console.log("Grade: C");
} else {
    console.log("Grade: F");
}

Nested Conditionals

Nested conditions are when one conditional statement is placed inside another, allowing for more complex decision-making based on multiple conditions.

Nested If statement

let userLoggedIn = true;
let isAdmin = false;
if (userLoggedIn) {
    if (isAdmin) {
        console.log("Welcome, Admin!");
    } else {
        console.log("Welcome, User!");
    }
} else {
    console.log("Please log in.");
}

Nested Loops

for (let i = 0; i < 3; i++) {
    for (let j = 0; j < 3; j++) {
        console.log(`i: ${i}, j: ${j}`);
    }
}