# C++ program to calculate the area of the square with and without using function

In this example, you will learn about C++ program to calculate the area of square with and without using a function.

For the better understanding of the program, you should know about following C++ programming topic :

The formula to calculate the area of a square is:

`Area = length * length`

## Example: C++ program to calculate the area of square

``````/* program to calculate the area of square */
#include <iostream>
using namespace std;

int main() //function main begins program execution
{
int square_area, square_side;

cout << "Enter the side of square:";
cin >> square_side;

square_area = square_side * square_side;

cout << "Area of Square: " << square_area << endl;
return 0;
} // end main
``````

Output ## Example: C++ program to calculate the area of square using function

``````/* program to calculate the area of square using function */
#include <iostream>
using namespace std;

void area(); //function prototype

int main() //function main begins program execution
{
area(); //function call
return 0;
} // end main

void area() //called function
{
int square_area, square_side;

cout << "Enter the side of square:";
cin >> square_side;

square_area = square_side * square_side;

cout << "Area of Square: " << square_area << endl;
} //end function area
``````

Output 