An overview of the basics of using functions in C. Source code: github.com/portfoliocourses/c.... Check out www.portfoliocourses.com to build a portfolio that will impress employers!
Great video, I love the fact you take the time to explain the core functionality behind things, metioning relationships and comparisons between other things we've already learned, instead of just glossing over code.
Thank you very much. It's one thing to read and understand a book, but it's also very easy to lose your way when implementing those concepts from a book. This put me back on track, and now I understand why I am making mistakes with my functions.
Can we actually call out mult() function inefficient, if eventually the compiler produces assembly code that multiplies by addition for all high-level multiplications?
Hi, thanks for the video, may I know why is there a "0" in "return 0" and "int result = 0"? What does the 0 mean? Is there any other video I can see to find out why?
Great question Jeremy! :-) This video explains the main function return values: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-CBfhcRQVpf8.html. In the "mult" function in this video, we start result off at zero with int result = 0, but then use the add function to continually add y to the result, before finally returning the result.
Great question Marek! :-) You could technically put the whole function definition before main and it will work. You could do this if you had multiple functions as well. But then if you have many functions defined, you would need to either scroll through or read through them before finding the main function. If we use function prototypes, when reading our file from top to bottom, at the top of are file we are made aware of the functions that will be defined, and then we would next see the main function. From a readability perspective, this is generally going to be much easier for a programmer to read and understand. :-)
Hello, you mentioned the variable result cannot the be used outside of the add function. It appears again in mult however. Is the program/compiler going to know both result variables are different even though they appear in two functions? Thank you
Great question! :-) So even though they have the same name, those are two different variables called result, each belonging to a different function (the “scope” of the variables). This video covers variable scope in more detail: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-IVJoByfBcZs.html
These can be pretty tricky concepts unfortunately! But basically if we have something like 4 x 7 = 28, we can think of it as 7 + 7 + 7 +7 = 28. In other words, adding four 7 values together. So we have an add() function that will return the result of adding a and b, so if we pass it add(0,7) it will return 7. If we pass it add(7,7) it will return 14. If we pass it add(14,7) it will return 21. And if we pass it add(21,7) it will return 28. Our mult() function performs the multiplication by repeatedly calling add 'x' number of times using the loop, just like that example above, with add(result,y), where y is the right operand of our multiplication x * y with mult(x,y). And the function starts off result at 0, and calls add with add(result,y) each time, but it stores the value returned by the call to add back into result. So if the first time result is 0 then we'll call add(0,7) and it's going to return 7 (which gets stored into result). And the NEXT time we call add we'll have add(7,7) which is going to return 14 (which again gets stored into result). And then we call add(14,7) and get 21, and then again with add(21,7) to get 28. And at that point we'll have done the x=4 adds, and the loop will stop, and the function returns the result. Hopefully this helps somewhat! :-)
This was helpful sir.. I really appreciate.. for the fact that you respond to every message that comes in the comment section is something to appreciate.. thank you sir
Great question! 🙂 So we declare i in the for loop itself with: for (int i = 0; i < x; i++) result = add(result, y); Specifically where it says "int i = 0;". This is another way of declaring a variable. The variable i will have the "scope" of the for loop, which means the variable will "exist" inside the for loop only.
@@PortfolioCourses that question of the boi jumped into my mind and i was like no way its gonna work until i saw that i = 0 xdd , was a relly fun short story . u earned my sub
I would have to see your code to know what's going on there. :-) Maybe you can paste it in as a comment? In order to return a value from a function the regular way, we do need to use a return statement of some kind.
@@PortfolioCourses check the code=i removed return keyword bt the result is still getting printed #include int main() { int fun1(int s1,int s2){ int s3=s1+s2; } int output=fun1(5,12); printf("the result is: %d ", output); }
