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How does the method get these answers?

// first answer becomes 36 // second answer becomes 88 i'm confused on how the result works and how the for loop is working within this program. static int Pow(int x, int y=2) { int result = 1; for (int i = 0; i < y; i++) { result *= x; } return result; } static void Main(string[] args) { Console.WriteLine(Pow(6)); Console.WriteLine(Pow(3, 4)); }

15th Sep 2017, 10:17 AM
Devin Blevins
Devin Blevins - avatar
3 Answers
+ 11
Pow(6) - Only one parameter is passed, default value for second parameter is used (2). for (int i = 0; i < y; i++) { result *= x; } Loop runs for values of i = 0, 1. result *= x is executed two times. Hence result stores 6 * 6. Value 36 is returned. Pow(3, 4) - Two parameters passed. Loop runs for values of i = 0, 1, 2, 3. result *= x is executed four times. Hence result stores 3 * 3 * 3 * 3. Value 81 is returned.
15th Sep 2017, 10:28 AM
Hatsy Rei
Hatsy Rei - avatar
+ 2
Pow(6) When this is called the second argument isn't passed, so the Pow method will use the default value of 2 for y. static int Pow(int x, int y=2) // y is an optional parameter and defaults to the value of 2 if a value is not passed when Pow is called In the for loop y is equal to 2 and i has an initial value of 0. 0 < 2 is true so the body of the loop is entered result is equal to 1 and x is the value that was passed when the Pow method was called. It has a value of 6. result *= x is the same as result = result * 6 result = 1 * 6 So now result is equal to 6 then the value of i is incremented by the for loop (i++) and is now equal to 1 1 < 2 is again true so the body of the for loop is ran again result = 6 * 6 result = 36 then the value of i is incremented again (i++) and is now equal to 2 2 < 2 is now false so the for loop is exited The value of result is returned to the Console.WriteLine(36); and 36 is output. Then flow moves on to Console.WriteLine(Pow(3, 4)); This call works in the same way, but y will equal 4 instead of the default value of 2. See if you can think through the loop with these values step by step.
15th Sep 2017, 10:37 AM
ChaoticDawg
ChaoticDawg - avatar
+ 2
So for loops in general and in this for loop: -you are defining an integer I and setting it to 0 (int i = 0) part -Then you are setting the condition for it to follow (i < y) -lastly, you are incrementing the value by 1 so you don't get stuck in an infinite loop [Also you need to use the condition and incrementation together, for example, you should not check i < 10 and have i-1 because then you will have an infinite loop too because i will never reach 10 and thus the loop will run forever or until it uses up all your memory and crashes more here: https://en.wikipedia.org/wiki/Infinite_loop] You can rewrite it like this with a while loop if it helps (people tell me they can understand while loops better but they are quite similar) static int Pow(int x, int y=2) { int result = 1; //set intial position/value for the loop to start at int i = 0; //check if the condition is valid and keep running while it is valid while (i < y) { result *= x; //increment up to the next number getting closer to the condition we set for the loop. i++; } return result; } then you can read it for yourself -result is set to 1 - i is set to 0 -while i is less than y: => multiple result by x (y number of times because that is how many times the loop will run due to the condition you made) => then increment by 1 -once loop ends give me the calculated results Then you can print it out learn more about for loops: https://www.tutorialspoint.com/csharp/csharp_for_loop.htm
15th Sep 2017, 12:31 PM
Kyrizu
Kyrizu - avatar