# C++ Program to Find Perimeter of a Rectangle

Howdy readers, today you will learn how to write a C++ program to find the perimeter of a rectangle.

The perimeter of a rectangle is the total length or distance of its boundary on all sides. It is twice the sum of its length and width, and it is calculated with the help of a formula: Perimeter = 2(length + width).

This tutorial computes the perimeter of a rectangle using the following methods:

1. Using Standard Method
2. Using Function

So, without any delay, letâ€™s begin this tutorial.

## C++ Program to Find Perimeter of a Rectangle

C++ Program

```// C++ Program to Find Perimeter of a Rectangle
#include <iostream>
using namespace std;

int main(){

// Taking input
cout << "Enter the length of the rectangle: ";
cin >> length;
cout << "Enter the breadth of the rectangle: ";

// Perimeter of a rectangle
perimeter = 2 * (length + breadth);

// Display perimeter
cout << "The perimeter of the rectangle is: " << perimeter << endl;

return 0;
}
```

Output

```Enter the length of the rectangle: 15
Enter the breadth of the rectangle: 18
The perimeter of the rectangle is: 66
```

Explanation

```    float length, breadth, perimeter;
```

We have declared three float data type variables named `length`, `breadth` and `perimeter`.

```    cout << "Enter the length of the rectangle: ";
cin >> length;
cout << "Enter the breadth of the rectangle: ";
```

The length and breadth of the rectangle are entered by the user. The entered values get stored in the `length` and `breadth` named variables.

```    perimeter = 2 * (length + breadth);
```

The perimeter of the rectangle is calculated using the formula: Perimeter = 2(length + width).

```    cout << "Perimeter of the rectangle is: " << perimeter << endl;
```

At last, the perimeter of the rectangle is printed on the screen using the `cout` statement.

## C++ Program to Find Perimeter of a Rectangle Using Function

C++ Program

```// C++ Program to Find Perimeter of a Rectangle Using Function
#include <iostream>
using namespace std;

float periRect(float a, float b){
return 2 * (a + b);
}

int main(){
float l, b, perimeter;

// Taking input
cout << "Enter the length of the rectangle: ";
cin >> l;
cout << "Enter the breadth of the rectangle: ";
cin >> b;

// Calling out function
perimeter = periRect(l, b);

// Display output
cout << "Perimeter = " << perimeter;

return 0;
}
```

Output

```Enter the length of the rectangle: 7
Enter the breadth of the rectangle: 5
Perimeter = 24
```

Explanation

```float periRect(float a, float b){
return 2 * (a + b);
}
```

In this program, we have declared and defined a function named `periRect` which passes the dimensions of the rectangle through arguments and returns the perimeter.

```    perimeter = periRect(l, b);
```

Then, we call out the custom function in the main function. This gives us the value of the perimeter. This value gets stored in the `perimeter` named variable.

## Conclusion

Today you learned how to write a C++ program to find the perimeter of a rectangle.

If you have any questions related to the program, comment down your question in the comment section.