# C++ Notes: Switch: Simple Calculator

Here is a very simple calculator.

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    // switch/infix-calc.cpp - Simple calculator.
    //    Illustrates switch and continue statements.
    //    Not robust (eg, doesn't check for division by 0).
    // Fred Swartz 10 Aug 2003

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

    int main() {
        int  left, right;   // Operands
        char oper;          // Operator
        int  result;        // Resulting value

        while (cin >> left >> oper >> right) {
            switch (oper) {
                case '+': result = left + right;
                          break;
                case '-': result = left - right;
                          break;
                case '*': result = left * right;
                          break;
                case '/': result = left / right;
                          break;
                default : cout << "Bad operator '" << oper << "'" << endl;
                          continue;  // Start next loop iteration.
            }
            cout << result << endl << endl;
        }

        return 0;
    }