04 - Array Cardio Day 1

Array Cardio Day 1

In this first cardio day we make use of some of the Array build-in methods:

• map
• sort
• reduce

Notes

When working with sort, two directions:

• Ascendent: 1 indicates that goes down in the array:

   arr.sort((a, b) => a > b ? 1 : -1);

• Descendent: -1 indicates that goes up in the array:

   arr.sort((a, b) => a > b ? -1 : 1);

When working with reduce, the key to be able to proccess different data types is the initialize value:

const data = ['car', 'car', 'truck', 'truck', 'bike', 'walk', 'car', 'van', 'bike', 'walk', 'car', 'van', 'car', 'truck' ],
	sol = data.reduce((obj, item) => {
		if(!obj[item]) 
			obj[item] = 0;
		obj[item]++;
		return obj;
	}, {});