Input Validation for only positive integers C++

[USN2ENG]

Homework Statement

I created a program that will calculate the factorial of the number entered and am having a hard time getting it to not accept decimals or fractions.

#include <iostream>
using namespace std;
int main (){
	int q=0;
	int number = 0;
		
	cout<<"Please enter a positive whole number:"<<endl;
	/*cin>>number;*/
	while(!(cin>>number)||number<0){
		cin.clear();
		while(cin.get()!='\n'){ [B]/*Also, this was the only thing I could find to stop it from looping Invalid input endlessly but I am not sure exactly what this is doing, if anyone could explain that would help a lot*/[/B]
			continue;
			cin>>number;
		}
		cout<<"Invalid Input"<<endl;
		}
	int x = number;	
	int y=1;
	while(x>1){
		y = y*x;
		x--;
		}
	cout<<y;
	return 0;
}

The Attempt at a Solution

I am 2 months into my first programming class ever and I can't seem to figure out how to get around the fact that if I enter '3.2' or '3/2' it will only look at the '3' and not the '.2', or '/2'. I would probably need to change the data type to float or something but then I am not sure how to use the input validation after that. I tried using isdigit(number) but that was not working either.
I have googled just about everything I could think of but I am not sure where to go. If anyone can point me in the right direction that would help immensely! Thanks!
Chuck

 

[Mark44]

I'm not sure what your problem is. Your input variable is number, which is type int. When your program prompts you to enter a positive integer, if you type 3.2, the program will accept only the integer part, not the decimal portion. Isn't this what you want?

Also, if you type in 3/2, your haven't written your program to parse arithmetic expressions such as 3/2 or 5+ 7 and so on.

 

[USN2ENG]

I wanted it to see that the decimal was there and then declare it invalid. Basically I wanted it to see if anything other than an integer is there, it is then invalid.

I was able to do it with:

 cout<<"Please enter a positive whole number:"<<endl;
	
	while((cin>>number).fail()||number<0 ||cin.peek() != '\n'){
		cin.clear();
		while(cin.get()!='\n'){
			continue;
			cin>>number;
		}
		cout<<"Invalid Input"<<endl;
		}

Thanks for all the help!