---
id: 5e302e8ce003129199103c79
title: Part 22
challengeType: 0
---
# --description--
Now let's simplify the `reduce()` callback function by refactoring it.
Essentially, the current callback function is `(accumulator, currentValue) => { return accumulator + currentValue }`. Since there's only one expression in the function body, we can omit the `{}`. Additionally, we can omit the `return` keyword since that is implicit when using arrow function syntax.
So the function can be simplified to just `(accumulator, currentValue) => accumulator + currentValue`.
Replace the current callback function argument in the `reduce()` function with the simplified callback function from above.
# --hints--
See description above for instructions.
```js
assert(
code
.replace(/\s/g, '')
.match(
/reduce\(\(accumulator\,currentValue\)\=\>accumulator\+currentValue\,0\)/
)
);
```
# --seed--
## --before-user-code--
```html
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title></title>
<meta name="description" content="" />
<meta name="viewport" content="width=device-width, initial-scale=1" />
<link rel="stylesheet" href="styles.css" />
</head>
<body>
<div class="container">
<form id="calorie-form">
<h2 class="center">Calorie Counter</h2>
<div class="grid">
<legend>Sex</legend>
<div>
<input type="radio" name="sex" id="female" value="F" checked />
<label for="female">
Female (2,000 calories)
</label>
<div>
<input type="radio" name="sex" id="male" value="M" />
<label for="male">
Male (2,500 calories)
</label>
</div>
</div>
</div>
<div class="grid" id="entries">
Breakfast
<input
type="number"
min="0"
class="cal-control"
id="breakfast"
/><br />
Lunch
<input type="number" min="0" class="cal-control" id="lunch" /><br />
Dinner <input type="number" min="0" class="cal-control" id="dinner" />
</div>
<button type="button" class="btn-add" id="add">
Add Entry
</button>
<button type="submit" class="btn-solid" id="calculate">
Calculate
</button>
<button type="button" class="btn-outline" id="clear">
Clear
</button>
</form>
<div id="output"></div>
</div>
</body>
</html>
```
## --after-user-code--
```html
</body>
</html>
```
## --seed-contents--
```html
<script>
document.getElementById('calorie-form').onsubmit = calculate;
function calculate(e) {
e.preventDefault();
const total = Array.from(document.getElementsByClassName('cal-control'))
.map(meal => Number(meal.value))
.reduce((accumulator, currentValue) => {
//console.log({ accumulator });
//console.log({ currentValue });
return accumulator + currentValue;
}, 0);
//console.log({ total });
}
</script>
```
# --solutions--
```html
<script>
document.getElementById('calorie-form').onsubmit = calculate;
function calculate(e) {
e.preventDefault();
const total = Array.from(document.getElementsByClassName('cal-control'))
.map(meal => Number(meal.value))
.reduce((accumulator, currentValue) => accumulator + currentValue, 0);
}
</script>
```