//**************************************************************************
//
// Copyright (c) 1997-1999.
//      Richard D. Irwin, Inc.
//
// This software may not be distributed further without permission from
// Richard D. Irwin, Inc.
//
// This software is distributed WITHOUT ANY WARRANTY. No claims are made
// as to its functionality or purpose.
//
// Authors:  James P. Cohoon and Jack W. Davidson
// Date:     7/1/98
// Purpose:  Compute a simple arithmetic expression
// Revised:  Keith Shomper 9/25/03
//           - reformatted for use in class lecture
//
//**************************************************************************

#include <iostream>
using namespace std;

int main() {
	int LeftOperand, RightOperand;  // Integers to combine in simple expression
	int Result;                     // Result of expression (i.e., the answer)

	// Expression operator--valid operators are +, -, / and *
	char Operator;

	// prompt for simple expression 
	cout << "Please enter a simple expression (number operator number): ";
	cin >> LeftOperand >> Operator >> RightOperand;

	// compute desired operation
	switch (Operator) {
		case '+':
			Result = LeftOperand + RightOperand;
			break;

		case '-':
			Result = LeftOperand - RightOperand;
			break;

		case '*':
			Result = LeftOperand * RightOperand;
			break;

		// the divide case requires we check to make sure the RightOperand is
		// not zero, since division by zero is undefined
		case '/':
			if (RightOperand != 0)
				Result = LeftOperand / RightOperand;
			else {
				cout << LeftOperand << " / "
				 << RightOperand << " cannot be computed:"
				 << " denominator is zero." << endl;
				return 1;
			}
			break;

		default:
			cout << Operator
 			     << " is unrecognized operation." << endl;
			return 1;
	}

	// display result
	cout << LeftOperand << " " << Operator << " "
	     << RightOperand << " equals " << Result << endl;

	return 0;
}