#    
## Overview
The **```kotlin.collections``` package** is part of Kotlin's standard library and contains all collection types, such as ```Map```, ```List```, ```Set```, etc.

The package provides the **```ArrayList``` class**, which is a mutable list and uses a dynamic, resizable array as the backing storage.


## The `containsAll()` method
The `ArrayList` class contains the **`containsAll()` method**, which checks for the presence of all elements of the specified input collection in the array list.

## Syntax
```
fun containsAll(elements: Collection<E>): Boolean
```

## Parameters 
The `containsAll()` method takes the collection of elements to search as input.

## Return value
`containsAll()` returns ```true``` if all the elements of the input collection are present in the array list, and `false` otherwise.

## Things to note
- `ArrayList` follows the sequence of insertion of elements.

- `ArrayList` is allowed to contain duplicate elements.

The illustration below shows the function of the `containsAll()` method.

fun main(args : Array<String>) {
    val monthList = ArrayList<String>()
    
    monthList.add("January")
    monthList.add("February")  
    monthList.add("March")  
    monthList.add("April")  
    monthList.add("May") 
    println("Printing ArrayList elements--")  
    println(monthList)  

    val inputList = ArrayList<String>()
    inputList.add("January")
    inputList.add("February")     
    println("Printing Input collection elements--")  
    println(inputList)  
    val result = monthList.containsAll(inputList)
    
    println("Is input list present in the array list? : ${result}")  
    
}

#    
## Explanation
- Line 2: We create an empty array list named `monthList` to store the strings.

- Line 4 to 8: We use the `add()` method to add a few month names to the `ArrayList` object, such as `"January"`, `"February"`, `"March"`, `"April"`, and `"May"`.

- Line 12 to 14: We create a new array list `inputList` and add month names `"January"` and  `"February"` to it.

- Line 17: We call the `containsAll()` method and pass the `inputList` collection as the parameter. The `containsAll()` method returns `true`, as all elements of the input collection are present in the array list.

We use the `println()` function of the `kotlin.io` package to display the `Arraylist` elements and result of the `containsAll()` method.

What is the ArrayList.containsAll() method in Kotlin?

Overview

The containsAll() method

Syntax

Parameters

Return value

Things to note

Explanation

The `containsAll()` method