C PROGRAMMING PROGRAM • BASICS & INPUT/OUTPUT

Calculate Rectangle Area and Perimeter

Learn how to calculate rectangle area and perimeter using a clear C program.

BeginnerArithmeticGeometryVariables

PROBLEM UNDERSTANDING

Input and expected output

Sample input

8 5

Sample output

Area = 40.00
Perimeter = 26.00

COMPLETE C PROGRAM

Complete C implementation

#include <stdio.h>

int main(void)
{
    double length, width;

    printf("Enter length and width: ");
    scanf("%lf %lf", &length, &width);
    printf("Area = %.2f\n", length * width);
    printf("Perimeter = %.2f\n", 2.0 * (length + width));
    return 0;
}

CURRENT STEP

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SELECTED LINE

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EXPECTED OUTPUT FOR THE SAMPLE

Area = 40.00
Perimeter = 26.00

0%Step 0 of 0

PROGRAM EXPLANATION

Algorithm and explanation

Read the required input values.
Multiply length and width for area, then double their sum for perimeter.
Display the computed result.

Multiply length and width for area, then double their sum for perimeter.

EFFICIENCY

Time and space complexity

Time complexity

O(1)

Auxiliary space

O(1)

DEBUGGING CHECKLIST

Common mistakes

Check this

Use the correct format specifier for every variable.

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Initialize variables before using their values.

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Check braces, semicolons and input order carefully.

Try it yourself

Practice: Run the program with the sample input, predict its output, and then test one boundary case of your own.