Computer Science 112

Honors Credit

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Day 2 Notes: Argument Passing

c++ program must have a main. must return int.
everything can be on one line.
if/else if/else. Chaining by statements. Switch is better.

  #include <iostream>
  #include <cassert>

  using namespace std;

  // // unsigned factorial(unsigned n) {
  // //   // if ((n == 0) or (n == 1)) {
  // //   //   return 1;
  // //   // }
  // //   // else {
  // //   //   unsigned total = 1;
  // //   //   for (unsigned i = 2; i <= n; i++) {
  // //   //     total *= i;
  // //   //   }
  // //   //   return total;
  // //   // }
  // //   unsigned result = 1;
  // //   for (unsigned number = 2 ; number <= n ; number++) result *= number;
  // //   return result;
  // // }

  // void exchange(int &a, int &b) {
  //   int c = a;
  //   a = b;
  //   b = c;
  // }

  // void rotate(int &a, int &b, int &c) {
  //   int d = a;
  //   a = b;
  //   b = c;
  //   c = d;
  // }

  void print(const string &genome) {
    for(unsigned i = 0 ; i < genome.size() ; i ++) {
      cout << genome[i];
    }
  }

  int main() {

    // int x = 11, y = 22, z = 33;
    // exchange(x, y);
    // assert(x == 22);
    // assert(y == 11);

    // rotate(x, y, z);

    // assert(x == 11); assert (y == 33); assert(z == 22);

    // // assert(factorial(0) == 1);
    // // assert(factorial(1) == 1);
    // // assert(factorial(2) == 2);
    // // assert(factorial(3) == 6);
    // // assert(factorial(4) == 24);
    // // assert(factorial(5) == 120);

    // cout << "Tests succeeded." << endl;

    print("ACTAGCTA");
  }

parameter passing modes
- default: pass by value, parameter is a distinct variable, into which the argument is copied. Changes to the parameter have no effect on the argument back in the caller.
- pass by reference, place an ampersand between a parameter's type and name. Think of these parameters as aliases of the arguments.
- call-by-const-reference: the parameter is a read only reference to the parameter.
primitive types (use pass-by-value):
- int
- double
- char
- float
- unsigned
- long
- short
Composite types (classes and structs) (use pass-by-const-value):
- string
- stream
- cstream
- complex

Day 3 Notes: Classes

Modeling payroll

employees
- name
- paid vacation days
- sick days
- identifier (number)
salaried employees
- salary
hourly employees
- wage
- hours worked
- overtime

  #ifndef EMPLOYEETESTER_H_
  #define EMPLOYEETESTER_H_

  class EmployeeTester {
  public:
    EmployeeTester();
    void runTests();
    void testConstructors();
  };

  #endif

  #include "EmployeeTester.h"
  #include <iostream>
  using namespace std;

  void EmployeeTester::EmployeeTester() {

  }

  void EmployeeTester::runTests() {
    cout << "Testing class Employee..." << endl;
    testConstructors();
    cout << "All tests passed." << endl;
  }

  void EmployeeTester::testConstructors() {
    cout << "- consturcotrs... " << flush;
    Employee emp;
    assert(emp.getId() == 0);
    assert(emp.getName() == "");
    assert(emp.getVacation() == 0);
    cout << "Passed!" << endl;
  }

  #include <iostream>
  #include <cassert>
  #include "EmployeeTester.h"
  using namespace std;

  int main () {
    EmployeeTester et;
    et.runTests();
  }