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Devendra Devendra
Devendra Devendra

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JavaScript Loops: A Beginner's Guide

Introduction

Loops are essential constructs in JavaScript that empower developers to iterate over data, perform repetitive tasks, and control the flow of their programs. In this beginner-friendly guide, we'll explore three types of loopsβ€”for, while, and do-whileβ€”and introduce concepts like break, continue, and nested loops.


1. for Loop:

The for loop is a versatile construct that allows you to iterate a specific number of times. It consists of three parts: initialization, condition, and iteration.

for (let i = 0; i < 5; i++) {
  console.log("Iteration:", i);
}
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2. while Loop:

The while loop continues iterating as long as a specified condition evaluates to true. It's suitable when the number of iterations is unknown beforehand.

let count = 0;

while (count < 3) {
  console.log("Count:", count);
  count++;
}
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3. do-while Loop:

Similar to the while loop, the do-while loop executes its block of code at least once, even if the condition is initially false.

let x = 5;

do {
  console.log("Value of x:", x);
  x--;
} while (x > 0);
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4. break Statement:

The break statement allows you to exit a loop prematurely, terminating its execution.

for (let i = 0; i < 10; i++) {
  if (i === 5) {
    break; // Exit the loop when i reaches 5
  }
  console.log("Value of i:", i);
}
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5. continue Statement:

The continue statement skips the rest of the loop's code and moves to the next iteration.

for (let i = 0; i < 5; i++) {
  if (i === 2) {
    continue; // Skip iteration when i is 2
  }
  console.log("Value of i:", i);
}
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6. Nested Loops:

Nested loops involve placing one loop inside another. This technique is powerful for working with multidimensional data or performing complex iterations.

for (let i = 0; i < 3; i++) {
  for (let j = 0; j < 2; j++) {
    console.log("Nested Loop - i:", i, "j:", j);
  }
}
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Conclusion:

Understanding JavaScript loops and control flow constructs is a crucial step for any beginner programmer. Experiment with for, while, and do-while loops, and discover the versatility of break and continue statements. As you gain confidence, explore the world of nested loops, mastering these fundamental building blocks to enhance your ability to solve diverse programming challenges.

*Keep Grinding And all ezy! *

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