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## Manipulate Entries
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### Instructions
Create 3 functions which work like the `.filter`, `.map` and `.reduce` array methods, but for the **entries** in the grocery cart.
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- `filterEntries`: filters using both key and value.
- `mapEntries`: changes the key, the value or both.
- `reduceEntries`: reduces the entries.
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Create 3 additional functions that use your previously created functions and take an object as input:
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- `totalCalories`: that will return the total calories of a cart.
- `lowCarbs`: that leaves only those items which are lower than 50 grams.
- `cartTotal`: that will give you the right amount of calories, proteins... and **all the other** items in your grocery cart.
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> Think about the shape of `Object.entries()`
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### Code provided
> The provided code will be added to your solution, and does not need to be submitted.
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```js
// small database with nutrition facts, per 100 grams
// prettier-ignore
const nutritionDB = {
tomato: { calories: 18, protein: 0.9, carbs: 3.9, sugar: 2.6, fiber: 1.2, fat: 0.2 },
vinegar: { calories: 20, protein: 0.04, carbs: 0.6, sugar: 0.4, fiber: 0, fat: 0 },
oil: { calories: 48, protein: 0, carbs: 0, sugar: 123, fiber: 0, fat: 151 },
onion: { calories: 0, protein: 1, carbs: 9, sugar: 0, fiber: 0, fat: 0 },
garlic: { calories: 149, protein: 6.4, carbs: 33, sugar: 1, fiber: 2.1, fat: 0.5 },
paprika: { calories: 282, protein: 14.14, carbs: 53.99, sugar: 1, fiber: 0, fat: 12.89 },
sugar: { calories: 387, protein: 0, carbs: 100, sugar: 100, fiber: 0, fat: 0 },
orange: { calories: 49, protein: 0.9, carbs: 13, sugar: 9, fiber: 0.2, fat: 0.1 },
}
```
### Usage
Here is a possible script to test your functions:
```js
const groceriesCart = { orange: 500, oil: 20, sugar: 480 }
console.log('Total calories:')
console.log(totalCalories(groceriesCart))
console.log('Items with low carbs:')
console.log(lowCarbs(groceriesCart))
console.log('Total cart nutional facts:')
console.log(totalCart(groceriesCart))
```
And its output:
```console
Total calories:
2112.2
Items with low carbs:
{ oil: 20 }
Total cart nutional facts:
{
orange: {
calories: 245,
protein: 4.5,
carbs: 65,
sugar: 45,
fiber: 1,
fat: 0.5
},
oil: {
calories: 9.6,
protein: 0,
carbs: 0,
sugar: 24.6,
fiber: 0,
fat: 30.2
},
sugar: {
calories: 1857.6,
protein: 0,
carbs: 480,
sugar: 480,
fiber: 0,
fat: 0
}
}
```
### Notions
- [filter](https://devdocs.io/javascript/global_objects/array/filter)
- [map](https://devdocs.io/javascript/global_objects/array/map)
- [reduce](https://devdocs.io/javascript/global_objects/array/reduce)
- [entries](https://devdocs.io/javascript/global_objects/object/entries)
- [fromentries](https://devdocs.io/javascript/global_objects/object/fromentries)