import java.io.*;

class TidyArithmetic {
	
	static InputStreamReader isr;
	static BufferedReader comingIn;
	static PrintWriter goingOut;
	static final String allowableChars = "+-*/";
	
	public static void main ( String [ ] args ) throws Exception {
		
		initialiseIO();
		
		char op ; // space to hold a character rep some arithmetic operator
		int x , y ; // space to store input
		double answer = 0 ; // space for answer, poss decimal because of div
		
		x = getInt() ;
		op = getOP() ;
		y = getInt() ;
		
		answer = doCalc(x, y, op);
		
		System.out.println ( "The value of " +x+ " " +op+ " " +y+ " is " +answer) ;
		System.out.println ( "Thanks for using \"Multiplier\".  Do come again!" ) ;
		
		tidyUpIO();
		
	} // end of main method
	
	public static void initialiseIO() {
		isr = new InputStreamReader ( System.in ) ;
		comingIn = new BufferedReader ( isr ) ;
		goingOut = new PrintWriter ( System.out , true ) ;
	} // end of initliseIO method
	
	public static void tidyUpIO() throws IOException {
		isr.close();
		comingIn.close();
		goingOut.close();
	} // end of tidyUpIO method
	
	public static double doCalc ( int x, int y, char op) {
		double temp;
		switch ( op ) {
		case '+' :  temp = x + y ;  break ;
		case '-' :  temp = x - y  ;  break ;
		case '*' :  temp = x * y  ;  break ;
		case '/' :  temp = y!=0 ? (double)x/y : Double.NaN; break;
		default : System.out.println( "Sorry, I didn’t understand what you meant ... bye-bye!" ) ; 
		          temp = Double.NaN ;
		} // end switch statement interpreting the arithmetic operation to be performed
		return temp;
	} // end of doCalc method
	
	public static int getInt () throws IOException {
		int temp = 0, numberOfFails = 0;
		String tryAgain = "Sorry, I didn't understand that as an integer -- please try again." ;
		String genug = "Sorry, a bad day?  ... too many errors.  Try again another time!";
		boolean messedup = false;
		do {
			goingOut.println ( "Please enter an integer" ) ;
			try {
				temp = Integer.parseInt ( comingIn.readLine( ) ) ;
				messedup = false;
			}
			catch (NumberFormatException nfe) {
				messedup = true;
				numberOfFails++; // to limit the number of bad attempts
				goingOut.println( numberOfFails < 3 ? tryAgain : genug );
			}
		} while (messedup && numberOfFails < 3);
		
		if (messedup) System.exit(1);
		
		return temp;
	} // end of getInt method
	
	public static char getOP () throws IOException {
		int numberOfFails = 0;
		boolean knownChar = false;
		String tryAgain = "Sorry, I didn't understand your operator -- please try again, choosing from "
			+ allowableChars.toString();
		String genug = "Sorry, a bad day?  ... too many errors.  Try again another time!";
		char temp = '4'; // anything stupid to keep the complier happy!
		do {
			goingOut.println ( "Please enter an operator" ) ;
			temp = ( comingIn.readLine( ) ).charAt(0) ;
			for (int i=0; i<allowableChars.length(); i++)
				if (temp == allowableChars.charAt(i)) knownChar = true;
			if (!knownChar)
				goingOut.println( ++numberOfFails < 3 ? tryAgain : genug );
		}  while (!knownChar && numberOfFails < 3);
		
		if (!knownChar) System.exit(2);
		return temp;
	} // end of getOP method
	
} // end of class Arithmetic