How to add an element in Vector using vector::push_back

In this article we will discuss how to add element in a vector.

std::vector provides a member function to push an element at the end i.e.

void push_back (const value_type& val);

It will push the element in the end of list. As, this function adds the element, so it also increases the size of vector by 1.

Check out following example of push_back with a vector of strings i.e.

#include <iostream>
#include <vector>
#include <string>

int main() {
	// Creating a vector of int;
	std::vector<std::string> vecOfStr;

	std::cout << "Size of Vector = " << vecOfStr.size() << std::endl;

	// Push an element in vector, it will be appended in the last
	vecOfStr.push_back("AAA");
	vecOfStr.push_back("BBB");
	vecOfStr.push_back("BBB");

	std::cout << "Size of Vector = " << vecOfStr.size() << std::endl;

	// Now lets print the content of vector,
	for (std::string data : vecOfStr)
		std::cout << data << std::endl;

	return 0;
}

Output:

Size of Vector = 0
Size of Vector = 3
AAA
BBB
BBB

The above code uses the c++11’s newly introduced for loop. To compile the above code use following command,

g++ --std=c++11 example.cpp