### Attempting to make a factorial program has ended poorly

Hello, I'm trying to teach myself to code and I've always found the best way to learn was through doing. However in my attempt to make a fairly straightforward program(my first) I have clearly done something horribly wrong. Can anyone offer guidance as to what key concept I've messed up?
Thanks :)

 ``12345678910111213141516171819202122232425`` ``````#include using namespace std; int factorial(int f)//int f being the input number to be put through the program { int fac = f;//fac is the output int x = f; for(x = f; x=0; x-1)//x is to keep track of the loop { int fac = fac * x; cout<> y; int z = factorial(y); cout<< z; cin.ignore(); return 0; }``````
The last expression in your for loop doesn't do anything. Did you mean `x-=1` or `--x`?

Line 11 creates a new variable called fac each iteration of the loop that is different from the fac on line 7. Just use the fac you declared on line 7 inside the for loop.
I've made those changes however the output is now the same as the input.
 ``123456789101112131415161718192021222324`` ``````#include using namespace std; int factorial(int f)//int f being the input number to be put through the program { int fac = f;//fac is the output int x = f; for(x = f; x=0; x=x-1)//x is to keep track of the loop { fac = fac * x; cout<> y; int z = factorial(y); cout<< z; cin.ignore(); return 0; }``````
You aren't returning anything from the function, so what do you expect line 20 to do and line 21 to display?

 ``123456789`` ``````int factorial( int f ) { int result = f ; while ( --f > 1 ) result *= f ; return result ; }``````
I did originally have it returning the value but i wanted to have the cout so i could check if my loop was working.
Why do you not need curly brackets around the while in the example above?
You need curly brackets (which indicate a compound statement) only when the block of code you wish to execute consists of multiple statements. If the code you wish to execute for a loop consists of only one statement, the brackets aren't needed, although some folks consider it good practice to include them anyway.
Thank you.
One last quick question; I haven't seen the syntax in line 6 what do I need to read up on, as a google search isn't very helpful.
` result *= f;`

is equivalent to:

` result = result * f ; `

I would strongly suggest buying a book if you're serious about learning C++.

http://stackoverflow.com/questions/388242/the-definitive-c-book-guide-and-list
Learning C++ is part of a course I'm taking this semester, but in saying that the course caters for some who really shouldn't be touching a computer so we'll see what happens. Thanks for the advice you've been excellent
There's another problem in your for statement:

 ``123`` `````` for(x = f; x=0; x=x-1)//x is to keep track of the loop // ^^^ // Using single '=' sign means assignment, not comparison ``````

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