feat: finish chapter 3, program 1

meson.build

@@ -21,3 +21,4 @@ c_2_lab_3 = executable('c_2_lab_3', 'src/chapter_2/lab_3/main.cpp', install: tru
 c_2_program_1 = executable('c_2_program_1', 'src/chapter_2/program_1/main.cpp', install: true)
 
 c_3_lab_1 = executable('c_3_lab_1', 'src/chapter_3/lab_1/main.cpp', install: true)
+c_3_program_1 = executable('c_3_program_1', 'src/chapter_3/program_1/main.cpp', install: true)

src/chapter_3/program_1/main.cpp

@@ -0,0 +1,278 @@
+#include <algorithm>
+#include <array>
+#include <iostream>
+#include <stdexcept>
+#include <string>
+#include <unordered_map>
+
+using namespace std;
+
+class Date {
+private:
+  unsigned day;
+  unsigned month;
+  string monthName;
+  unsigned year;
+
+public:
+  // creates the date January 1st, 2000.
+  Date();
+
+  /* parameterized constructor: month number, day, year
+      - e.g. (3, 1, 2010) will construct the date March 1st, 2010
+
+      If any of the arguments are invalid (e.g. 15 for month or 32 for day)
+      then the constructor will construct instead a valid Date as close
+      as possible to the arguments provided - e.g. in above example,
+      Date(15, 32, 2010), the Date would be corrected to Dec 31st, 2010.
+      In case of such invalid input, the constructor will issue a console error
+     message:
+
+      Invalid date values: Date corrected to 12/31/2010.
+      (with a newline at the end).
+  */
+  Date(unsigned m, unsigned d, unsigned y);
+
+  /* parameterized constructor: month name, day, year
+     - e.g. (December, 15, 2012) will construct the date December 15th, 2012
+
+      If the constructor is unable to recognize the string argument as a valid
+     month name, then it will issue a console error message:
+
+      Invalid month name: the Date was set to 1/1/2000.
+      (with a newline at the end).
+
+      If the day argument is invalid for the given month (but the month name was
+     valid), then the constructor will handle this error in the same manner as
+     the other parameterized constructor.
+
+      This constructor will recognize both "december" and "December"
+      as month name.
+  */
+  Date(const string &mn, unsigned d, unsigned y);
+
+  /* Outputs to the console (cout) a Date exactly in the format "3/15/2012".
+     Does not output a newline at the end.
+  */
+  void printNumeric() const;
+
+  /* Outputs to the console (cout) a Date exactly in the format "March 15,
+     2012". The first letter of the month name is upper case, and the month name
+     is printed in full - January, not Jan, jan, or january. Does not output a
+     newline at the end.
+  */
+  void printAlpha() const;
+
+private:
+  /* Returns true if the year passed in is a leap year, otherwise returns false.
+   */
+  bool isLeap(unsigned y) const;
+
+  /* Returns number of days allowed in a given month
+     -  e.g. daysPerMonth(9, 2000) returns 30.
+     Calculates February's days for leap and non-leap years,
+     thus, the reason year is also a parameter.
+  */
+  unsigned daysPerMonth(unsigned m, unsigned y) const;
+
+  /* Returns the name of a given month
+     - e.g. name(12) returns the string "December"
+  */
+  string name(unsigned m) const;
+
+  /* Returns the number of a given named month
+     - e.g. number("March") returns 3
+  */
+  unsigned number(const string &mn) const;
+};
+
+// Implement the Date member functions here
+Date::Date() {
+  this->day = 1;
+  this->month = 1;
+  this->year = 2000;
+}
+
+bool Date::isLeap(unsigned y) const {
+  return ((y % 4 == 0 && y % 100 != 0) || y % 400 == 0);
+}
+
+unsigned Date::daysPerMonth(unsigned m, unsigned y) const {
+  const unsigned int ODD_MONTHS[] = {1, 3, 5, 7, 8, 10, 12};
+  const unsigned int EVEN_MONTHS[] = {4, 6, 9, 11};
+
+  if (find(begin(ODD_MONTHS), end(ODD_MONTHS), m) != end(ODD_MONTHS)) {
+    return 31;
+  }
+  if (find(begin(EVEN_MONTHS), end(EVEN_MONTHS), m) != end(EVEN_MONTHS)) {
+    return 30;
+  }
+
+  // leap year
+  if (this->isLeap(y)) {
+    return 29;
+  }
+
+  return 28;
+};
+
+string Date::name(unsigned m) const {
+  unordered_map<unsigned int, string> months;
+
+  months[1] = "January";
+  months[2] = "February";
+  months[3] = "March";
+  months[4] = "April";
+  months[5] = "May";
+  months[6] = "June";
+  months[7] = "July";
+  months[8] = "August";
+  months[9] = "September";
+  months[10] = "October";
+  months[11] = "November";
+  months[12] = "December";
+
+  try {
+    return (months.at(m));
+  } catch (std::out_of_range const &) {
+    return "NONE";
+  }
+};
+
+unsigned Date::number(const string &mn) const {
+  string mnLowered = mn;
+  mnLowered.at(0) = tolower(mn.at(0));
+
+  unordered_map<string, unsigned int> months;
+
+  months["january"] = 1;
+  months["february"] = 2;
+  months["march"] = 3;
+  months["april"] = 4;
+  months["may"] = 5;
+  months["june"] = 6;
+  months["july"] = 7;
+  months["august"] = 8;
+  months["september"] = 9;
+  months["october"] = 10;
+  months["november"] = 11;
+  months["december"] = 12;
+
+  try {
+    return (months.at(mnLowered));
+  } catch (std::out_of_range const &) {
+    return 999;
+  }
+};
+
+Date::Date(unsigned m, unsigned d, unsigned y) {
+  this->day = d;
+  this->month = m;
+  this->year = y;
+
+  if (m < 1) {
+    this->month = 1;
+  }
+
+  if (m > 12) {
+    this->month = 12;
+  }
+
+  if (d < 1) {
+    this->day = 1;
+  }
+
+  if (d > this->daysPerMonth(this->month, y)) {
+    this->day = this->daysPerMonth(this->month, y);
+  }
+
+  if (this->day != d || this->month != m || this->year != y) {
+    cout << "Invalid date values: Date corrected to " << this->month << "/"
+         << this->day << "/" << this->year << "." << endl;
+  }
+}
+
+Date::Date(const string &mn, unsigned d, unsigned y) {
+  Date date;
+  auto m = this->number(mn);
+
+  if (m != 999) {
+    date = Date(m, d, y);
+    this->day = date.day;
+    this->month = date.month;
+    this->year = date.year;
+  } else {
+    cout << "Invalid month name: the Date was set to 1/1/2000." << endl;
+    this->day = 1;
+    this->month = 1;
+    this->year = 2000;
+  }
+}
+
+void Date::printNumeric() const {
+  cout << this->month << "/" << this->day << "/" << this->year;
+};
+
+void Date::printAlpha() const {
+  cout << this->name(this->month) << " " << this->day << ", " << this->year;
+};
+
+// Don't change the code below this line.
+// You may comment them out if you want to build your own test harness
+// while in develope mode, but you will need these to pass tets in submit mode.
+
+Date getDate();
+
+int main() {
+
+  Date testDate;
+  testDate = getDate();
+  cout << endl;
+  cout << "Numeric: ";
+  testDate.printNumeric();
+  cout << endl;
+  cout << "Alpha:   ";
+  testDate.printAlpha();
+  cout << endl;
+
+  return 0;
+}
+
+Date getDate() {
+  int choice;
+  unsigned monthNumber, day, year;
+  string monthName;
+
+  cout << "Which Date constructor? (Enter 1, 2, or 3)" << endl
+       << "1 - Month Number" << endl
+       << "2 - Month Name" << endl
+       << "3 - default" << endl;
+  cin >> choice;
+  cout << endl;
+
+  if (choice == 1) {
+    cout << "month number? ";
+    cin >> monthNumber;
+    cout << endl;
+    cout << "day? ";
+    cin >> day;
+    cout << endl;
+    cout << "year? ";
+    cin >> year;
+    cout << endl;
+    return Date(monthNumber, day, year);
+  } else if (choice == 2) {
+    cout << "month name? ";
+    cin >> monthName;
+    cout << endl;
+    cout << "day? ";
+    cin >> day;
+    cout << endl;
+    cout << "year? ";
+    cin >> year;
+    cout << endl;
+    return Date(monthName, day, year);
+  } else {
+    return Date();
+  }
+}