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Small Error??

closed account (3vX4LyTq)
I'm writing a program that does factorials. It is supposed to cout all the factorials up to the integer that the user enters. Example:

Input
Enter integer (enter non numeric input to quit):

Output
1! = 1 = 1
2! = 2 x 1 = 2
3! = 3 x 2 x 1 = 6
4! = 4 x 3 x 2 x 1 = 24
5! = 5 x 4 x 3 x 2 x 1 = 120

I think I did something wrong with my while loop on lines 20-29

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#include <iostream>
using namespace std;                      


int main()
{
int counter = 0;
int numb = 0;
	cout << "Enter integer (enter non numeric input to quit): ";

	cin>>numb;
	counter = numb;
	long long result = 1;                     
	while(cin >> numb)                    
	{    

       if (numb == 0)                      
        {
        	cout << "0! = 1";                                  
        }
        while(counter!=0){
	    for (int i = 1; i <= numb; i++) 
	    {                    
	    	result = result * i;           
	    }

	    cout << numb << "! = " << result << endl << endl;   
        
	    counter--;                      
        }
	   cout << "Enter integer (enter non numeric input to quit): ";
    }                       
    cout << "Done" << endl << endl;
         
}


If you input 5, output is

5! = 120

4! = 2880

3! = 17280

2! = 34560

1! = 34560
Last edited on
closed account (48T7M4Gy)
Instead of resetting result to 1 at the start of each new number, you are continuing to multiply it. eg you calculate 5! ok but for 4! you are multiplying 4! by 5! ...
closed account (3vX4LyTq)
Okay, kemort. I tried to fix that by resetting int result.
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while(cin >> numb)                    
	{    

       if (numb == 0)                      
        {
        	cout << "0! = 1";                                  
        }
        while(counter!=0){
	    for (int i = 1; i <= numb; i++) 
	    {                    
	    	result = result * i;           
	    }

	    cout << numb << "! = " << result << endl << endl;   
      numb--; 
	    counter--;    
	    result = 1;
        }
    }

Now it kind of works

5

5! = 120

4! = 24

3! = 6

2! = 2

1! = 1

Yay! Now, I just need to show the math in the output...
bird1234 (126)
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#include <iostream>
using namespace std;


int main()
{
int counter = 0;
int numb = 0;
	cout << "Enter integer (enter non numeric input to quit): ";

	long long result = 1;
	while(cin >> numb)
	{
       counter = numb;
       if (numb == 0)
        {
        	cout << "0! = 1";
        }
        while(counter!=0){
	    for (int i = 1; i <= counter; i++)
	    {
	    	result = result * i;
	    }

	    cout << counter << "! = " << result << endl << endl;

	    counter--;
	    result=1;
        }
	   cout << "Enter integer (enter non numeric input to quit): ";
    }
    cout << "Done" << endl << endl;
    return 0;
}



Enter integer (enter non numeric input to quit): 5
5! = 120

4! = 24

3! = 6

2! = 2

1! = 1

Enter integer (enter non numeric input to quit):


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