C Program for Area And Perimeter Of Rectangle

Given a length and breadth of a rectangle we have to find its area and perimeter.

Rectangle is a 2-D figure containing four sides and four angles of 90 degrees each. All the sides of rectangle are not equal − only the opposite sides of a rectangle are equal. The diagonals in a rectangle also are of the same length.

Syntax

Area = Length × Breadth
Perimeter = 2 × (Length + Breadth)

Algorithm

The formulas for calculating rectangle properties are −

• Area: Length × Breadth
• Perimeter: 2 × (Length + Breadth)

Example: Using Functions

This program demonstrates calculation of area and perimeter using separate functions −

#include <stdio.h>

/* Function to calculate area */
int area(int length, int breadth) {
    return length * breadth;
}

/* Function to calculate perimeter */
int perimeter(int length, int breadth) {
    return 2 * (length + breadth);
}

int main() {
    int length = 20;
    int breadth = 30;
    
    printf("Length: %d, Breadth: %d
", length, breadth);
    printf("Area of rectangle is: %d
", area(length, breadth));
    printf("Perimeter of rectangle is: %d
", perimeter(length, breadth));
    
    return 0;
}

Length: 20, Breadth: 30
Area of rectangle is: 600
Perimeter of rectangle is: 60

Example: Using User Input

This example takes length and breadth from the user −

#include <stdio.h>

int main() {
    float length, breadth, area, perimeter;
    
    printf("Enter length of rectangle: ");
    scanf("%f", &length);
    printf("Enter breadth of rectangle: ");
    scanf("%f", &breadth);
    
    area = length * breadth;
    perimeter = 2 * (length + breadth);
    
    printf("\nRectangle Properties:
");
    printf("Length: %.2f
", length);
    printf("Breadth: %.2f
", breadth);
    printf("Area: %.2f
", area);
    printf("Perimeter: %.2f
", perimeter);
    
    return 0;
}

Key Points

• Rectangle area formula: Length × Breadth
• Rectangle perimeter formula: 2 × (Length + Breadth)
• Use float for decimal precision in measurements
• Functions make code modular and reusable

Conclusion

Calculating rectangle area and perimeter in C is straightforward using basic arithmetic operations. Functions improve code organization and allow for easy reuse of calculation logic.