# Basic C Exercises

**C program to find perimeter of a rectangle**

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.

**Required knowledge**

Data Types in c,
Input/Output in C,
C Operators,
Variables
**Perimeter of rectangle**

Perimeter of rectangle is given by the below formula

#### Perimeter of rectangle

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.

In addition, never write statement like 2 * (length + width) as 2(length + width). It will generate a compilation error.

**Output:**

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