Print a Staircase Pattern with Nested Loops in JavaScript

The challenge

Write staircase(n) that prints n lines. Line 1 has one #, line 2 has two, and so on. Then call staircase(4).

Example

#
##
###
####

Try it

Write your answer below, then press Check my answer. Your code runs right here in your browser, and the tests tell you what works.

Your solution

It prints

What the tests check

It prints:
```
#
##
###
####
```

Hints

Stuck? Open one hint at a time. Try again after each one.

Hint 1

An outer loop for each line, and an inner loop (or "#".repeat(i)) to build that line.

A solution

There’s always more than one right way. Read it, make sure you understand it, then try writing it yourself without looking.

Show one possible solution

Solution

function staircase(n) {
  for (let i = 1; i <= n; i++) {
    let line = "";
    for (let j = 0; j < i; j++) {
      line += "#";
    }
    console.log(line);
  }
}

staircase(4);

Learn what you need

This exercise uses what Grade 5: Loops: Doing Things Over and Over teaches. Read those notes first if any of it is new.

Print a staircase pattern with nested loops