Exploring Nested Loops in TypeScript

Introduction

Our path today leads through the realm of Exploring Nested Loops in TypeScript . Think of these as revolving mechanisms within each other, much like solar systems within galaxies, each having its own distinct motion. We'll delve deep and learn how to efficiently manipulate these loops in TypeScript by the end of this tutorial.

We'll begin by unveiling the format of a nested for loop in TypeScript: TypeScript for (let i = 0; i < 3; i++) {for (let j = 0; j < 3; j++) {console.log(`i = ${i}, j = ${j}`); // e.g., "i = 0, j = 0"}} /* Prints: i = 0, j = 0 i = 0, j = 1 i = 0, j = 2 i = 1, j = 0 i = 1, j = 1 i = 1, j = 2 i = 2, j = 0 i = 2, j = 1 i = 2, j = 2 */ For each progression of i from 0 to 2, we run through j from 0 to 2 and display the respective values of i and j .

Just as with for loops, while loops can also be composed of nested loops: TypeScript let i = 0; while (i < 3) {let j = 0; while (j < 3) {console.log(`i = ${i}, j = ${j}`); // e.g., "i = 0, j = 0" j++;} i++;} /* Prints: i = 0, j = 0 i = 0, j = 1 i = 0, j = 2 i = 1, j = 0 i = 1, j = 1 i = 1, j = 2 i = 2, j = 0 i = 2, j = 1 i = 2, j = 2 */ In this case, too, the inner loop j runs in its entirety for every single iteration of the outer loop i .

To illustrate nested loops, let's observe a two-dimensional (2D) array — essentially an array of arrays: TypeScript let matrix: number[][] = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]; for (let i = 0; i < matrix.length; i++) { // Iterating over each row. let row = ''; for (let j = 0; j < matrix[i].length; j++) { // Iterating over each element in the row. row += `${matrix[i][j]} `;} console.log(row);} /* Prints: 1 2 3 4 5 6 7 8 9 */ For every i row (outer loop), an inner loop goes through every element within that row.

Here is another example of a nested for loop that creates a numerical pyramid: TypeScript for (let i = 1; i <= 5; i++) { // The first loop denotes each level of the pyramid. let row = ''; for (let j = 1; j <= i; j++) { // The second loop adds numbers to each level. row += `${j} `;} console.log(row); // Prints each level of the pyramid.} /* Prints: 1 1 2 1 2 3 1 2 3 4 1 2 3 4 5 */ for (let i = 1; i <= 5; i++) { // The first loop denotes each level of the pyramid. let row = ''; for (let j = 1; j <= i; j++) { // The second loop adds numbers to each level. row += `${j} `;} console.log(row); // Prints each level of the pyramid.} /* Prints: 1 1 2 1 2 3 1 2 3 4 1 2 3 4 5 */

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