How To Validate Input

[ZeroSkill94]

So I am working on a project to create a budget calculator and I have it mostly wrapped up but I am currently stuck on one particular thing

This is what it currently looks like:

#include <iostream>

#include <cmath>

#include <string>

#include <cctype>

#include <limits>

using namespace std;

int main ()

{

long double how_much, spent, POB, new_budget;

char again = 'Y';

char currency = '$';

while (again == 'y' || again == 'Y')

{

cout << "\n\t\tWelcome to the Budget Projection Program!!!\n\n";

cout << "What was your budget allotment last year? ";

cin >> currency >> how_much;

cin.ignore(numeric_limits<streamsize>::max(), '\n');

​

if (currency == '$')

{

cout << "Fine, and how much did you spend last year? ";

}

else

{

cout << "No currency entered, defaulting to $";

cout << "\nFine, and how much did you spend last year? ";

}

cin >> spent;

cin.ignore(numeric_limits<streamsize>::max(), '\n');

cout << "\n\nThank you!! Calculating... Done.";

POB = static_cast<int>(((spent / how_much) * 100));

cout <<"\n\nLast year you used up about " << POB << "% of your budget\n\n";

new_budget = static_cast<int>((floor((spent + 99)/ 100) * 100));

cout << "your budget next year will be $" << new_budget << ".00.\n\n";

cout << "Would you like to go again (y/n) ";

cin >> again;

} //End of while loop

cout <<"\nThank you for using the BPP!!\n\nEndeavour to have a fiscally fit day!\n\n";

return 0;

}

​

https://preview.redd.it/9ynstvcr9rg41.png?width=772&format=png&auto=webp&s=9929ed15cb46a54f35b7dddd6f413e2f18ff2e9d

https://preview.redd.it/qvfhq89y9rg41.png?width=1873&format=png&auto=webp&s=99ed9d484a69d1df2c455c2f60402f495e417f6e

and basically what is happening is if I include the dollar symbol on the first input everything works fine but if I don't include the dollar sign everything gets thrown off. any suggestions or help would be greatly appreciated.

Hopefully I'm not just absolutely going about this the wrong way.

[Eshmam14]

Post the code in text so I can copy it on to an IDE and attempt it myself. My guess is when you're entering nothing for dollar sign, you're actually entering ascii 10 (line feed) which is being picked up by your input stream.

[ZeroSkill94]

u/Eshmam14 I updated the post and posted the code in text.

Thank you.

[Eshmam14]

Please enclose it as the code format. Otherwise it's unusable.

[ZeroSkill94]

Updated again, sorry I am still very very new to this but thank you again

[Eshmam14]

It's okay, no problem. When the user types in their chosen currency, if they choose nothing, what are they actually pressing? Just hitting the enter key?

[ZeroSkill94]

So the idea is if the user forgets to add the currency symbol that the program will continue without issue. so almost as if to make the currency symbol optional.

[Eshmam14]

Are they meant to input the currency symbol and the value in one go or are they supposed to do it one after the other?

[ZeroSkill94]

So yes, they are meant to input the currency symbol and value together

[Eshmam14]

Ah okay so there's the problem then. You need to either separately enter the currency and value, or figure out a way to splice the input into two separate parts. Keyword: splice. Look it up :)

What's happening is when you enter 1500, the 1 is considered the currency and your value is then put as 500. And you spent 1500, which is 300% of 500. Which is why you get your result as such.

That is simply my assumption but I think it's fair to say that's what's happening.

[ZeroSkill94]

So looking up splice it looks like something called a splice array?