Solution Review: Calculate the Area and Perimeter
Follow the step-by-step instructions to calculate the area and perimeter.
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Solution
Press the RUN button and see the output of the code given below!
#include <stdio.h>void areaPeri(double, double, double, double * , double * , double * , double * );int main() {double r, l, b, ac, pc, ar, pr;r = 2.5, l = 4.9, b = 6.8;areaPeri(r, l, b, & ac, & pc, & ar, & pr);printf("Area of circle = %f \nPerimeter of circle = %f\n", ac, pc);printf("Area of rectangle = %f \nPerimeter of rectangle = %f\n", ar, pr);return 0;}void areaPeri(double radius, double length, double breadth, double * cirArea,double * cirPeri, double * recArea, double * recPeri) {// Calculates area of circle* cirArea = 3.14 * radius * radius;// Calculates perimeter of circle* cirPeri = 2 * 3.14 * radius;// Calculates area of rectangle* recArea = length * breadth;// Calculates perimeter of rectangle* recPeri = 2 * (length + breadth);}
Explanation
The main function
The return statement returns only one value at a time. Using the pass by reference method, we can indirectly return multiple values from a function. Let’s see how we can do this!
Line 8: Here, we have made a mixed call to the function, areaPeri(). Values of r, l, and b are passed to the function. Whereas, we have passed the addresses of ac, pc, ar, and pr in cirArea, cirPeri, recArea, and recPeri, respectively.
📝 Note: In a mixed call, some of the parameters are passed by value and some of them are passed by reference.
Lines 9-10: Since we have access to the addresses of the actual arguments, any changes made to these arguments in the areaPeri() function would be reflected in the main() function. In this way, we can indirectly return multiple values from a function.
The areaPeri function
Lines 17-19: The formulas for calculating the area and perimeter of the circle are given below:
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