Homework- Modular overloaded functions to calculate area and perimeter of circle, rectangle and triangle.

2.1 SHAPES

#include <iostream>
#include <cmath>
using namespace std;

const long double pi = 3.141592654; 

void getDim (float&);
void getDim (float&, float&);
void getDim (float&, float&, float&);

float area (float);
float area (float, float);
float area (float, float, float);

float perim (float);
float perim (float, float);
float perim (float, float, float);

void display (float, float, int);

int main(){
	
	float rad, width, length, sideA, sideB, sideC, ansArea, ansPer;
	int shape;

do{
	cout << "AREA/PERIMETER CALCULATOR" <<endl;
	cout << "Select a shape: \nCircle (1) Rectangle (2) Triangle (3) Exit (4)\nEnter selection => ";
	cin >> shape;
		while (shape != 4 && shape != 3 && shape != 2 && shape != 1){
			cout << "Select a shape: \nCircle (1) Rectangle (2) Triangle (3) Exit (4)\nEnter selection => ";
			cin >> shape;
		}
	switch (shape){
		case 1:
			getDim (rad);
			ansArea = area (rad);
			ansPer = perim (rad);
			display (ansArea, ansPer, shape);
			break;
		case 2:
			getDim (width, length);
			ansArea = area (width, length);
			ansPer = perim (width, length);
			display (ansArea, ansPer, shape);
			break;
		case 3:
			getDim (sideA, sideB, sideC);
			ansArea = area (sideA, sideB, sideC);
			ansPer = perim (sideA, sideB, sideC);
			display (ansArea, ansPer, shape);
			break;
		default: break;
	}

}while (shape != 4);
	
	cout << "\nBye...";
	return 0;
}

void getDim (float& rad){
	cout << "Enter circle radius: ";
	cin >> rad;
		while (rad < 0){
		cout << "ERROR: radius may not be negative. Re-enter: ";
		cin >> rad;
		}
}

void getDim (float& length, float& width){
	cout << "Enter rectangle length: ";
	cin >> length;
		while (length < 0){
			cout << "ERROR: length may not be negative. Re-enter: ";
			cin >> length;
		}
	cout << "Enter rectangle width: ";
	cin >> width;
		while (width < 0){
			cout << "ERROR: width may not be negative. Re-enter: ";
			cin >> width;
		}
}

void getDim (float& sideA, float& sideB, float& sideC){
	cout << "Enter first side of triangle: ";
	cin >> sideA;
		while (sideA < 0){
			cout << "ERROR: side length may not be negative. Re-enter: ";
			cin >> sideA;
		}
	cout << "Enter second side of triangle: ";
	cin >> sideB;
		while (sideB < 0){
			cout << "ERROR: side length may not be negative. Re-enter: ";
			cin >> sideB;
		}
	cout << "Enter third side of triangle: ";
	cin >> sideC;
		while (sideC < 0){
			cout << "ERROR: side length may not be negative. Re-enter: ";
			cin >> sideC;
		}
}

float area (float rad){
	
	return (pi*(rad*rad));
}

float area (float length, float width){
	
	return (length*width);
}

float area (float sideA, float sideB, float sideC){
	double s;
	s = (sideA + sideB + sideC)/2;
	return (sqrt(s*(s-sideA)*(s-sideB)*(s-sideC)));
}

float perim (float rad){
	return (2*pi*rad);
}

float perim (float length, float width){
	return ((2*length)+(2*width));
}

float perim (float sideA, float sideB, float sideC){
	return (sideA + sideB + sideC);
}

void display (float ansArea, float ansPer, int shape){
	if (shape == 1){
		cout << "Circle ";
	}
	else if (shape == 2){
		cout << "Rectangle ";
	}
	else if (shape == 3){
		cout << "Triangle ";
	}

	cout << "Area = " << ansArea << " and perimeter " << ansPer << endl << endl;
}