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vector::max_size() function with example in C++ STL

C++ STL vector::max_size() function: Here, we are going to learn about the max_size() function of vector header in C++ STL with example.
Submitted by IncludeHelp, on May 13, 2019

C++ vector::max_size() function

vector::max_size() is a library function of "vector" header, it is used to get the maximum size of a vector, it returns the total number of elements that a vector can store.

Note: To use vector, include <vector> header.

Syntax

Syntax of vector::max_size() function

vector::max_size();

Parameter(s)

none – It accepts nothing.

Return value

size_type – It returns the maximum size of a vector as an unsigned integral type.

Sample Input and Output

Input:
vector<int> vector1{ 1, 2, 3, 4, 5 };

Function call:
cout << vector1.max_size();

Output:
4611686018427387903

C++ program to demonstrate example of vector::max_size() function

//C++ STL program to demonstrate example of
//vector::max_size() function

#include <iostream>
#include <vector>
using namespace std;

int main()
{
    vector<int> v1;

    //printing the max_size of the vector
    cout << "Maximum number of elements that can be stored: ";
    cout << v1.max_size() << endl;

    //pushing elements
    v1.push_back(10);
    v1.push_back(20);
    v1.push_back(30);
    v1.push_back(40);
    v1.push_back(50);

    //printing the max_size of the vector
    cout << "Maximum number of elements that can be stored: ";
    cout << v1.max_size() << endl;

    return 0;
}

Output

Maximum number of elements that can be stored: 4611686018427387903
Maximum number of elements that can be stored: 4611686018427387903

Reference: C++ vector::max_size()