# C++ map clear() function

C++ map clear() function is used to remove all the elements of the map container. It clears the map and sets its size to 0.

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## Example 1

Let's see a simple example to calculate the size of map before and after the clear operation.

Output:

```Initial size of map before clear operation = 5
Size of map after clear opearation = 0
```

In the above example, a map is initialized with 5 elements. Therefore, the size of the map is 5 but after the clear operation, size becomes 0.

## Example 2

Let's see a simple example to clear the elements of the map.

Output:

```mymap contains:
1 : Nikita
2 : Deep
3 : Ashish

mymap contains:
4 : Rajni
5 : Sunil
```

In the above example, after clear the map, we can add new elements without initialization.

## Example 3

Let's see a simple example to clear the elements of the map.

Output:

```m1 group has following members:
1 : Nikita
2 : Deep
3 : Ashish
m2 group has following members:
1 : Nidhi
2 : Priya
3 : Gitanjali
m3 group has following members:
1 : Rakesh
2 : Fruti
3 : Kamlesh

Which group do you want to delete?
1. m1
2. m2
3. m3

Group m2 has been cleared.
```

In the above example, there are three groups of a map and according to the user?s choice, one group has been deleted.

## Example 4

Let's see a simple example:

Output:

```1.
Fruit bucket has following fruits =
Apple : 190
Banana : 40
Orange : 120

Do you want to clear your fruit bucket?
Press 1 for Yes and 0 for No: 0
3 fruits in bucket

2.
Fruit bucket has following fruits =
Apple : 190
Banana : 40
Orange : 120

Do you want to clear your fruit bucket?
Press 1 for Yes and 0 for No: 1
0 fruits in bucket
```

In the above example, a fruit map is initialized with three fruits. Asking for clearing the map, if you enter 0 then fruit bucket has 3 elements or if you enter 1 then it will clear the fruit map and the size becomes 0.

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