题目1116：加减乘除

import java.io.IOException;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.FileReader;
import java.util.Scanner;


class Main
{
	public static final boolean DEBUG = false;
	
	public static long fac(int n) 
	{
		if (n == 0) return 1;
		return n * fac(n - 1);
	}
	
	public static void main(String[] args) throws IOException
	{
		Scanner cin;
		String op;
		int a = 0, b = 0;
		
		if (DEBUG) {
			cin = new Scanner(new FileReader("d:\\OJ\\uva_in.txt"));
		} else {
			cin = new Scanner(new InputStreamReader(System.in));
		}
		
		while (cin.hasNext()) {
			a = cin.nextInt();
			op = cin.next();
			if (op.compareTo("!") != 0) b = cin.nextInt();
			
			if (op.compareTo("+") == 0) {
				System.out.println(a + b);
			} else if (op.compareTo("-") == 0) {
				System.out.println(a - b);
			} else if (op.compareTo("*") == 0) {
				System.out.println(a * b);
			} else if (op.compareTo("/") == 0) {
				if (b == 0) {
					System.out.println("error");
				} else {
					System.out.println(a / b);
				}
			} else if (op.compareTo("!") == 0) {
				System.out.println(fac(a));
			} else if (op.compareTo("%") == 0) {
				if (b == 0) System.out.println("error");
				else System.out.println(a % b);
			}
		}
	}
}