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;
}