
There are few development tips for Javascript array operation, these tips will reduce your development time.

## 1. Initialize an array with default value

If you are working with fixed length of array and you need to initialize it with fixed value.
We have traditional way of initialzation but also we have alterative and it is a shortcut method.

**Initialize one dimensional array**
If you want to intialize one dimensional array of specified length and apply the default values.

```javascript
const oneArray = Array(6).fill('xxx');  
//["xxx", "xxx", "xxx", "xxx", "xxx", "xxx"]
```
**Initialize Multi-dimentsional array**

If you want to intialize multi-dimensional array of specified length and apply the default values.

```javascript
const multiArray = Array(6).fill(0).map(() => Array(5).fill('xxx'));
// [["xxx", "xxx", "xxx", "xxx", "xxx"], ["xxx", "xxx", "xxx", "xxx", "xxx"], ["xxx", "xxx", "xxx", "xxx", "xxx"], ["xxx", "xxx", "xxx", "xxx", "xxx"], ["xxx", "xxx", "xxx", "xxx", "xxx"], ["xxx", "xxx", "xxx", "xxx", "xxx"]]

```

## 2. Find Sum, Maximum and Minimum of an array.

It is a very tricky and this is a common question in most of interviews. 
To solve this we can use javascript standard function "reduce()".

*The reduce() method executes a reducer function for array element.*

```javascript
const sampleArray  = [51,14,17,28,39,32];
```

**Sum**
```javascript
sampleArray.reduce((a,b) => a+b);

//Result: 181
```

**Finding Maximum**
```javascript
sampleArray.reduce((a,b) => a > b ? a : b);  Math.max(...sampleArray)
//Result: 51
```

**Finding Minimum**
```javascript
sampleArray.reduce((a,b) => a < b ? a : b);  Math.min(...sampleArray)
//Result: 14
```

## 3. Empty an array

If you want to clear the values in the array variable then set the length equal to Zero.

```javascript
let array = ["J", "A", "V", "A", "S", "C", "R", "I", "P", "T"]
array.length = 0 
console.log(array)  // []
```

## 4. Split the word into an Array

We can split the word by given identifier, this is can be achieved by using <code>split()</code>

*Eg :- 1*
```javascript
let array = "JAVASCRIPT"
console.log(array.split(""))
Result //["J", "A", "V", "A", "S", "C", "R", "I", "P", "T"]
```
*Eg :- 2*
```javascript
let array = "JAVA-SCRIPT"
console.log(array.split("-"))
Result //["JAVA", "SCRIPT"]
```
the above are the two example of split function on different scenario.

## 5. Combine two or more arrays

If you want to Merge or Combine two or more arrays then use the <code>Spread Operator</code> or <code>Concat()</code>

<u>using Spread or Extension operator</u>
```javascript
const start = [1, 2] 
const end = [5, 6, 7] 
const result = [9, ...start, ...end, 8] // [9, 1, 2, 5, 6, 7 , 8]
```
<u>using concat method</u>
```javascript
const start = [1, 2, 3, 4] 
const end = [5, 6, 7] 
start.concat(end); // [1, 2, 3, 4, 5, 6, 7]
```


There are few development tips for Javascript array operation, these tips will reduce your development time.

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