# map max_size() in C++ STL

C++Server Side ProgrammingProgramming

In this article we will be discussing the working, syntax and examples of map::max_size() function in C++ STL.

## What is a Map in C++ STL?

Maps are the associative container, which facilitates to store the elements formed by a combination of key value and mapped value in a specific order. In a map container the data is internally always sorted with the help of its associated keys. The values in the map container are accessed by its unique keys.

## What is a map::max_size()?

map::max_size() function is an inbuilt function in C++ STL, which is defined in <map> header file. max_size() is used to return the maximum size of the map container.

This function is used to check the maximum number of values that a map container can hold. The size is like the potential of the container, hence there is no guarantee that it can reach that value or not.

## Syntax

Map_name.max_size();

## Parameter

This function accepts no parameter.

## Return value

This function returns the number of elements a container can hold.

Input

map<char, int> newmap;
newmap.max_size();

Output

Max size of map is: 461168601842738790

## Example

Live Demo

#include <bits/stdc++.h>
using namespace std;
int main(){
map<int, int> TP_1, TP_2;
TP_1.insert({ 0, 10 });
cout<<"Max size of map with elements is: " << TP_1.max_size();
cout<<"\Max size of map without elements is: " << TP_2.max_size();
return 0;
}

## Output

If we run the above code it will generate the following output −

Max size of map with elements is: 461168601842738790
Max size of map without elements is: 461168601842738790
Published on 14-Aug-2020 11:53:58