Write a C program to input length and width of a rectangle and calculate perimeter of the rectangle. How to find perimeter of a rectangle in C programming. Logic to find the perimeter of a rectangle if length and width are given in C programming.

**Example**

**Input**

Enter length: 5 Enter width: 10

**Output**

Perimeter of rectangle = 30 units

## Required knowledge

Operators, Data types, Defining Variables, Basic input/output

## Perimeter of rectangle

Perimeter of rectangle is given by the below formula

Where `l` is length and `w` is the width of rectangle.

## Logic to find perimeter of a rectangle

Below is the step by step descriptive logic to find perimeter of a rectangle

- Input length and width of the rectangle using
`scanf()`

function. Store it in two variables say`length`and`width`. - Calculate perimeter using formula for perimeter of rectangle
`perimeter = 2 * (length + width)`

. - Print the value of
`perimeter`.

## Program to find perimeter of rectangle

```
/**
* C program to find perimeter of rectangle
*/
#include <stdio.h>
int main()
{
float length, width, perimeter;
/*
* Input length and width of rectangle from user
*/
printf("Enter length of the rectangle: ");
scanf("%f", &length);
printf("Enter width of the rectangle: ");
scanf("%f", &width);
/* Calculate perimeter of rectangle */
perimeter = 2 * (length + width);
/* Print perimeter of rectangle */
printf("Perimeter of rectangle = %f units ", perimeter);
return 0;
}
```

**Note: ** Never forget to prioritize the order of operations using a pair of braces `(`

`)`

. Since, statements `perimeter = 2 * length + width`

and `perimeter = 2 * (length + width)`

will generate different results.

Read more - Precedence and associativity of operators

In addition, never write statement like `2 * (length + width)`

as `2(length + width)`

. It will generate a compilation error.

Enter length of the rectangle: 5 Enter width of the rectangle: 10 Perimeter of rectangle = 30.000000

Happy coding 😉

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