---
id: 5ddb965c65d27e1512d44dab
title: Part 18
challengeType: 0
dashedName: part-18
---
# --description--
The `reduce()` method takes a callback function with at least two arguments, an accumulator and a current value:
`function(accumulator, currentValue) { /* code to run */ }`
or using arrow functions:
`(accumulator, currentValue) => { /* code to run */ }`
Insert the above callback function as an argument in the `.reduce()` method.
# --hints--
See description above for instructions.
```js
assert(
code
.replace(/\s/g, '')
.match(/reduce\(\(accumulator\,currentValue\)\=\>\{\/\*codetorun\*\/\}\)/)
);
```
# --seed--
## --before-user-code--
```html