# break statement in JavaScript

The `break` statement allows you to terminate the loop early. Let's see when this might come in handy. Let's say we have a loop that prints the elements of an array to the console:

`let arr = [1, 2, 3, 4, 5]; for (let elem of arr) { console.log(elem); }`

Suppose we are faced with the task to determine whether the array contains the number `3`. If there is, we will display the word `'contains'` in the console (and if not, we will do nothing).

Let's solve our task:

`let arr = [1, 2, 3, 4, 5]; for (let elem of arr) { if (elem === 3) { console.log('contains'); } }`

The task is solved, however, there is a problem: after the number `3` has already been found, the array still keeps iterating over without sense, wasting valuable processor resources and slowing down our script.

It would be more optimal to terminate the work of our loop immediately after finding the number. This can be done using the special statement `break`, which allows you to terminate the loop ahead of schedule.

So, let's terminate the loop as soon as we meet the number `3`:

`let arr = [1, 2, 3, 4, 5]; for (let elem of arr) { if (elem == 3) { console.log('contains'); break; // get out of the loop } }`

The statement `break` can terminate any loop: the usual `for`, `while`, and so on.

Given an array of numbers. Run a loop that prints the elements of this array to the console one by one until an element with the value `0` is encountered. After that, the loop should finish work.

Given an array of numbers. Find the sum of the elements from the beginning of the array to the first negative number.

Given an array of numbers. Find the position of the first number `3` in this array (we assume that this number must be in the array).

Determine how many integers, starting with the number `1`, must be added to make the sum greater than `100`.

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