C Program – Area and Perimeter of Rectangle - Direct Calculation & Functions

Rectangle Area and Perimeter (Direct)

#include <stdio.h>
int main() {
    float length, breadth, area, perimeter;
    printf("Enter length and breadth of the rectangle: ");
    scanf("%f %f", &length, &breadth);
    area = length * breadth;
    perimeter = 2 * (length + breadth);
    printf("Area = %.2f\n", area);
    printf("Perimeter = %.2f\n", perimeter);
    return 0;
}
Enter length and breadth of the rectangle: 5 3
Area = 15.00
Perimeter = 16.00
        

This straightforward method calculates the area by multiplying length and breadth and computes the perimeter as twice the sum of the sides, printing both values for the user.

Rectangle Area and Perimeter Using Functions

#include <stdio.h>
float area(float l, float b) {
    return l * b;
}
float perimeter(float l, float b) {
    return 2 * (l + b);
}
int main() {
    float length, breadth;
    printf("Enter length and breadth of the rectangle: ");
    scanf("%f %f", &length, &breadth);
    printf("Area = %.2f\n", area(length, breadth));
    printf("Perimeter = %.2f\n", perimeter(length, breadth));
    return 0;
}
Enter length and breadth of the rectangle: 7.5 2.0
Area = 15.00
Perimeter = 19.00
        

Encapsulating the area and perimeter computations in separate functions makes the code modular and reusable. Each function takes length and breadth as parameters, returns the computed value, and is called from the main function.

Sai Kishore Randhi, author
About the author

Sai Kishore Randhi

Embedded systems, VLSI, and chip design

Sai Kishore writes about embedded systems, VLSI, chip design, and the programming concepts behind modern hardware.

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