Hi, I need to take an input called difference that can range from -7 to 7. I then need to enter a date. The program is supposed to output the date plus the difference.
#How to take input of dates without any libraries?
hoary dew
glass islandBOT
hoary dew
I have no clue where to start, and I'm not allowed to use AI. So my first question is how can I get an input of dates?
As a starter, im assuming that the year isnt a leap year, and all months have 30 days
latent pagoda
You take it in as a string and then you parse the string.
hoary dew
You take it in as a string and then you parse the string.
ok is it complicated though?
because so far we have covered these things, and I assume we are only allowed to use these: basics, if statements, real numbers.
latent pagoda
It's not complicated absolutely speaking.
hoary dew
assume I am only allowed to use the basic things, how would I do it?
I am thinking of this:
- Dissect the input into day month and year
- Add the difference to the day
- If the day goes over 30 then add one to the month
- If the month goes over 12, then add one to the year
would this be suitable?
It would soon get very complicated after considering different amount of days in each month
inner helm
"without any libraries" - what about the standard library?
Because there is date manipulation in it, going back all the way from C
inner helm
1. Dissect the input into day month and year
2. Add the difference to the day
3....
But doing it manually isn't that hard. Yes, you need to track the number of days in a month, but it's not crazy hard
latent pagoda
1. Dissect the input into day month and year
2. Add the difference to the day
3....
That's roughly the algorithm, the biggest thing in all of this is really just getting the date input.
hoary dew
But doing it manually isn't *that* hard. Yes, you need to track the number of da...
I'm mainly wondering how exactly Id do that
inner helm
Determine the number of days in a month. You could use a bunch of ifs to do that, or try to come up with something more clever
latent pagoda
For my reminder app I would convert the date into an integer representation and then convert it back into day, month and year for display.
inner helm
I'm mainly wondering how exactly Id do that
You could start with assuming 31 days in each month. And when that works, replace 31 with the proper amont
hoary dew
well, its not really difficult to take in the date using elementary methods, this is what I have done so far, but only for the month and day:
#include <iomanip>
using namespace std;
int date, difference, first, second, third, fourth, temp, day, month;
int main() {
cout << "Enter a difference: ";
cin >> difference;
cout << "Type in a date in day / month format: ";
cin >> date;
first = date / 1000;
temp = date / 100;
second = temp % 10;
temp = date / 10;
third = temp % 10;
fourth = date % 10;
day = 10*first + second;
month = 10*third + fourth;
}```yes, but how do I make it so for each individual month?
the above gives me the month and day, and all I have to do is add the difference
latent pagoda
You write code to determine the number of days in a month.
hoary dew
but if June has 30 days and July has 31, how does the code tell if it has 30 or 31 days?
hoary dew
You write code to determine the number of days in a month.
this is brilliant
latent pagoda
It can be literally: "If it's June then it's 30 days, if it's July then it's 31 days".
hoary dew
```#include <iostream>
#include <iomanip>
using namespace std;
int date, diffe...
also is there a way to make this have colours
latent pagoda
Add cpp to after the first three backticks.
inner helm
if (month == 1 || month == 3 || month == 5 .....) days = 31; else if (month == 4 || ....) days = 30;, and so on
hoary dew
#include <iostream>
#include <iomanip>
using namespace std;
int date, difference, first, second, third, fourth, temp, day, month;
bool days31;
int main() {
cout << "Enter a difference: ";
cin >> difference;
cout << "Type in a date in day / month format: ";
cin >> date;
first = date / 1000;
temp = date / 100;
second = temp % 10;
temp = date / 10;
third = temp % 10;
fourth = date % 10;
day = 10*first + second;
month = 10*third + fourth;
if (month == 1 || month == 3 || month == 5 || month == 7 || month == 8 || month == 10 || month == 12) {
days31 = true;
}
if (month == 2 || month == 4 || month == 6 || month == 7 || month == 9 || month == 11) {
days31 = false;
}
}```it seems to have shown in the output
latent pagoda
Enter after cpp.
hoary dew
oh nice
is it ok to use booleans or should I make (yet another varibale) equal to the number of days in the month
latent pagoda
February.
hoary dew
What of it?
latent pagoda
February has neither 30 nor 31 days.
latent pagoda
28 or 29.
hoary dew
but what of the days in each month, should I just make another variable for it
latent pagoda
Also you are going to need to use the number anyhow so it makes the most sense to come up with that number right away.
hoary dew
ah ok
just a min
#include <iostream>
#include <iomanip>
using namespace std;
int date, difference, first, second, third, fourth, temp, day, month, num_days_in_month, final_day, final_month;
bool days31;
int main() {
cout << "Enter a difference: ";
cin >> difference;
cout << "Type in a date in day / month format: ";
cin >> date;
first = date / 1000;
temp = date / 100;
second = temp % 10;
temp = date / 10;
third = temp % 10;
fourth = date % 10;
day = 10*first + second;
month = 10*third + fourth;
if (month == 1 || month == 3 || month == 5 || month == 7 || month == 8 || month == 10 || month == 12) {
num_days_in_month = 31;
}
if (month == 2 || month == 4 || month == 6 || month == 7 || month == 9 || month == 11) {
num_days_in_month = 30;
}
if (day + difference > num_days_in_month) {
final_day = num_days_in_month - (day + difference);
final_month = month + 1;
}
if (day + difference < num_days_in_month) {
final_day = day + difference;
}
cout << "The final date in day / month format is: " << final_day << " /" << final_month ;
}```This is what I got so far
but it output this
how could it output a negative day?
latent pagoda
Because your formula is wrong.
hoary dew
if (day + difference > num_days_in_month) {
final_day = (day + difference)- num_days_in_month;
final_month = month + 1;
}
if (day + difference < num_days_in_month) {
final_day = day + difference;
}
cout << "The final date in day / month format is: " << final_day << " /" << final_month ;
Ah, this should do it.
Now, lastly, Im just wondering before i try myself and ado you all goodnight, how would I work the negative?
latent pagoda
It's similar to getting past the end of the month, just in reverse.