Using Classes for Day of the Week - c++

Question

I have an assignment that essentially requires me to use a class to output the day of the week based upon input from the user EX: user enters sat (first three letters) --> output = This day of the week is: 6. We're also required for the program to also ouput the next six days following the day specified by the user, ex:
Input:
tue
Output:
This day of the week is: 2
This day of the week is: 3
This day of the week is: 4
This day of the week is: 5
This day of the week is: 6
This day of the week is: 7
This day of the week is: 1
My program is bit messy as I initially misunderstood the question. I was able to develop a functioning program that allows the user to input a number for the day, but not the first three letters as that part of the code seems not to be functioning whatsoever.
Any suggestions or solutions would be immensely appreciated. Thank you in advance.
#include <iostream>
#include <string>
using namespace std;
//
// Definition of the DayOfWeek class
//
class DayOfWeek
{
public:
DayOfWeek(int dayNum);
// Precondition: The parameter dayNum contains a valid
// day number (1 - 7)
// Postcondition: The member variable day has been set to
// the value of the parameter dayNum.
DayOfWeek();
// Sets the member variable month to 1 (defaults to January).
DayOfWeek(char fL, char sL, char tL);
void outputDayNumber();
// Postcondition: The member variable day has been output
// to the screen if it is valid; otherwise a "not valid"
// message is printed.
void outputDayLetters();
// Postcondition: The first three letters of the name of the
// day has been output to the screen if the day is
// valid (1 - 12); otherwise a message indicating the month
// is not valid is output.
DayOfWeek NextDay();
// Precondition: The month is defined and valid.
// Returns the next day as an object of type Day.
private:
int day;
};
int main()
{
//
// Variable declarations
//
int DayNum;
string DayWord;
char letter1, letter2, letter3; // first 3 letters of the day
char testAgain; // y or n - loop control
//
// Loop to test the next month function
//
do {
cout << endl;
cout << "Enter a day number: ";
cin >> DayNum;
DayOfWeek testDay(DayNum);
cout << endl;
cout << "This day ..." << endl;
testDay.outputDayNumber();
testDay.outputDayLetters();
DayOfWeek next = testDay.NextDay();
cout << endl;
cout << "Next day ..." << endl;
next.outputDayNumber();
next.outputDayLetters();
//
// See if user wants to try another month
//
cout << endl;
cout << "Do you want to test again? (y or n) ";
cin >> testAgain;
} while (testAgain == 'y' || testAgain == 'Y');
return 0;
}
DayOfWeek::DayOfWeek()
{
day = 1;
}
DayOfWeek::DayOfWeek(int dayNum)
{
if (dayNum >= 1 && dayNum <= 7)
day = dayNum;
else {
dayNum = 1;
}
}
void DayOfWeek::outputDayNumber()
{
if (day >= 1 && day <= 7)
cout << "Day: " << day << endl;
else
cout << "Error - The day is not valid!" << endl;
}
void DayOfWeek::outputDayLetters()
{
switch (day)
{
case 1:
cout << "1" << endl;
break;
case 2:
cout << "2" << endl;
break;
case 3:
cout << "3" << endl;
break;
case 4:
cout << "4" << endl;
break;
case 5:
cout << "5" << endl;
break;
case 6:
cout << "6" << endl;
break;
case 7:
cout << "7" << endl;
break;
default:
cout << "Error - the day is not valid!" << endl;
}
}
DayOfWeek::DayOfWeek(char firstL, char secondL, char thirdL)
{
/**
*check to for the first characters or letter of the day
*prints the day based on the characters user input
*check if the characters is valid
*/
if (firstL >= 65 && firstL <= 90) {
firstL += 32;
}
if (secondL >= 65 && secondL <= 90) {
secondL += 32;
}
if (thirdL >= 65 && thirdL <= 90) {
thirdL += 32;
}
if (firstL == 'm' && secondL == 'o' && thirdL == 'n') {
day = 1;
}
else if (firstL == 't' && secondL == 'u' && thirdL == 'e') {
day = 2;
}
else if (firstL == 'w' && secondL == 'e' && thirdL == 'd') {
day = 3;
}
else if (firstL == 't' && secondL == 'h' && thirdL == 'u') {
day = 4;
}
else if (firstL == 'f' && secondL == 'r' && thirdL == 'i') {
day = 5;
}
else if (firstL == 's' && secondL == 'a' && thirdL == 't') {
day = 6;
}
else if (firstL == 's' && secondL == 'u' && thirdL == 'n') {
day = 7;
}
else {
day = 0;
cout << "Invalid Day" << endl;
}
}
DayOfWeek DayOfWeek::NextDay() {
int d = (day % 7) + 1;
return DayOfWeek(d);
}
UPDATE:
Changed my code up entirely but still need to implement the next day and then
the next 6 days function.
NEW CODE :
#include <iostream>
#include <string>
using namespace std;
class DayOfWeek
{
string day;
public:
DayOfWeek();
DayOfWeek(string day_name);
void print_car(ostream& ins);
};
int main() {
string day_name;
cout << "Enter the first three letters of the day :" << endl;
cin >> day_name;
DayOfWeek my_car(day_name);
my_car.print_car(cout);
return 0;
}
DayOfWeek::DayOfWeek(string day_name) {
day = day_name;
}
void DayOfWeek::print_car(ostream& outs) {
if (day == "Mon" || day == "mon") {
outs << "This is day 1 of the week" << endl;
}
if (day == "Tue" || day == "tue") {
outs << "This is day 2 of the week" << endl;
}
if (day == "Wed" || day == "wed") {
outs << "This is day 3 of the week" << endl;
}
if (day == "Thu" || day == "thu") {
outs << "This is day 4 of the week" << endl;
}
if (day == "Fri" || day == "fri") {
outs << "This is day 5 of the week" << endl;
}
if (day == "Sat" || day == "sat") {
outs << "This is day 6 of the week" << endl;
}
if (day == "Sun" || day == "sun") {
outs << "This is day 7 of the week" << endl;
}
}
Final Update:
I am nearly at a final solution but I am having a issues declaring a
new object for the final part of my problem.
The code is here...
#include <iostream>
#include <string>
using namespace std;
class DayOfWeek
{
string day;
// int nday;
public:
DayOfWeek();
DayOfWeek(string day_name);
void print_day(ostream& ins);
};
int main() {
string day_name;
int nday;
cout << "Enter the first three letters of the day :" << endl;
cin >> day_name;
DayOfWeek week_day(day_name);
week_day.print_day(cout);
DayOfWeek next_day;
int d = _____;
int current = (d % 7) + 1;
int count = 0;
while (count < 7) {
next_day = DayOfWeek(current);
next_day.print_day(cout);
count++;
}
return 0;
}
DayOfWeek::DayOfWeek(string day_name) {
day = day_name;
}
void DayOfWeek::print_day(ostream& outs) {
int dayNumber = 0;
if (day == "Mon" || day == "mon") {
dayNumber = 1;
}
if (day == "Tue" || day == "tue") {
dayNumber = 2;
}
if (day == "Wed" || day == "wed") {
dayNumber = 3;
}
if (day == "Thu" || day == "thu") {
dayNumber = 4;
}
if (day == "Fri" || day == "fri") {
dayNumber = 5;
}
if (day == "Sat" || day == "sat") {
dayNumber = 6;
}
if (day == "Sun" || day == "sun") {
dayNumber = 7;
}
outs << "This is day " << dayNumber << " of the week." << endl;
}
I have some issue being able to convert the user inputted name of the day, into an integer that I can use to plug into the next_day function.
I am also having an error in the while loop
while (count < 7) {
next_day = DayOfWeek(current);
next_day.print_day(cout);
count++;
}
specifically line:
next_day = DayOfWeek(current);
The error says that there's no instance of DayOfWeek::DayOfWeek matching the argument list.
I feel like I'm nearly there if not for these couple of bumps.

Answer 1

Code below should do some of what you need.
Instead of using chars, I've used a string. That way you can compare the whole string in one go rather than 1 char at a time.
Also for comparing the input against the day-words, i have created an array of Strings. The index corresponds to the day, i.e 0=sunday, 1=monday etc.
This is neat for 2 reasons, we can compare with a loop easily, and as soon as we find the matching day, we just grab the index and there we have our day number. Store that number, and then we can return that for the day number, or use the day as an index in the array to return the day word instead.
Hopefully this is clear, you still need to make a function to return the next day, but the 3 letter input should work.
#include <iostream>
#include <cctype> // std::tolower
#include <algorithm> // std::transform
class DayOfWeek
{
private:
const static std::string days[7];
private:
int day;
public:
DayOfWeek();
DayOfWeek(int);
DayOfWeek(std::string);
void outputDayNumber();
void outputDayLetters();
};
// if we have an array of strings, we can use these for comparison and also Day value
const std::string DayOfWeek::days[7] = {"sun", "mon", "tue", "wed", "thu", "fri", "sat"};
DayOfWeek::DayOfWeek() {
}
DayOfWeek::DayOfWeek(int dayNum)
{
day = dayNum;
}
DayOfWeek::DayOfWeek(std::string dayWord)
{
day = 0; // set Sunday as default
// truncate the string to 3 letters
if (dayWord.length() > 3)
dayWord = dayWord.substr(0, 3);
// to lower case - makes comparison case insensitive
std::transform(dayWord.begin(), dayWord.end(), dayWord.begin(), [](unsigned char c) { return std::tolower(c);});
// compare with our list of strings, if none found, it will stay as default
for (int i = 0; i < 7; ++i)
if (days[i] == dayWord)
{
day = i;
break;
}
}
void DayOfWeek::outputDayLetters() {
std::cout << std::endl << "Day Letters: " << days[day];
}
void DayOfWeek::outputDayNumber() {
std::cout << std::endl << "Day Numbers: " << day;
}
int main()
{
int dayNum;
std::string dayWord;
std::cout << std::endl << "Enter a weekday: ";
std::cin >> dayWord;
std::cout << std::endl << "You entered " << dayWord;
DayOfWeek dayObject = DayOfWeek(dayWord);
dayObject.outputDayNumber();
dayObject.outputDayLetters();
}