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Part two of the challenge was the code, the logic for taking turns, so in this video, I'm going to

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go through the solutions for tasks three to five, starting with task three, which tells you to run

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a loop that goes through each turn.

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There are nine turns in a game of tic tac toe.

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So I'm going to create a loop that runs nine times for enties equal to zero I smaller than nine I a

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plus plus.

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And for now, we'll print the counter during each run.

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I know we didn't write a lot of code, but it's always a good idea to keep testing.

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I want to get you in the habit of doing that, so I'll run.

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First, it prints the grid and then it prints a bunch of numbers nine times.

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We can now remove the print statement, the next step is to create an if statement that runs code if

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it's X's turn, as well as an else plot that runs code if it's ostern, I left you with a hint to learn

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the parts explains when the counter is even, whereas O plays on the counter is Ezzard.

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A number is even if dividing it by two returns, the remainder of zero zero, I'm going to check if

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the number modulus two is equal to zero.

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Then I'll print.

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Turn X otherwise.

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Turno.

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All right, and that's really it for TASC three.

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Feel free to test your code.

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And as expected, it keeps changing turns.

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Now, before we read any more logic inside the final statements, we need to create some functions.

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So moving on to task for.

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Our next task is to write a function that lets the user choose a spot.

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So we'll follow our comment public static.

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The function returns an entero.

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The function is called ask user.

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And it receives one parameter, the board.

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In order to satisfy this area, we need to create an array and return it, but I don't feel like creating

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an array.

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This is actually a great time to employ the array trick that I left you in the cheat sheet.

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I provided you with the syntax and what this does is it offers a cool way to return a raise on the fly,

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so I'm going to follow the syntax and return a new integer array.

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Were the random values of 011 for now.

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Now, you know me, I like to keep testing my code as I write it.

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And there is still a lot of code we need to write for this function, so as you're writing it, we're

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going to call it for each turne ask user pass in the board and call the function for Ostern as well.

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Inside the function, I left you some instructions.

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First, we're going to ask the user to pick a spot on the grid in the form of a row and column number.

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If you go back to learn the part, pay attention to the output, the user writes each valley beside

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the question.

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Accordingly, I'm going to print the message using print, not print line.

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And since we're asking the user to input two values, we need to call upon Skinner, I declared Skinner

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for you at the level of the class so we should be able to access it from anywhere.

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And here, I'm going to use it to pick up the RO.

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The element in that row, i.e., the column.

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OK, I think we have enough to start seeing some pretty cool output, run your code.

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And you know what, I'm going to add some white space right after the Colin.

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I'll use controls to stop the output we run the code.

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Turn exile to zero zero and inside the row, I'll choose the first inducts.

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Here, I'll do Rosero second index, and this loop runs exactly nine times.

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So players can keep picking spots until the game ends.

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All right, good.

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After nine turns, the loop breaks.

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Now, instead of returning to random numbers, the function is going to return the spot that the user

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chooses.

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All right, there's another step for task force, but we can't do it yet right now, we need to populate

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the board with X's and O's.

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And that would be task five.

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During each turn, the function call returns an array of integers that contains the user spot, so we

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need to store that array in a variable.

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So I'm going to create a variable int spot.

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And whether it's Axis Turner O's turn, we're going to set the spot variable equal to the return value.

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We're going to use the spot variable to update the board.

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The first bracket specifies the row.

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And we know the road that the user chooses is index zero of our spot array.

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So we'll use that value to index the row and the column, the element in that row would be in the second

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index of our spot array.

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And if we're inside the statement, we're going to update that spot on the board to X and if we're inside

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or else it's OK turn.

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So we're going to update the spot that they choose on the board of.

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After the player picks their spot and we update the border Ray, we need to print the board and thank

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goodness we can just call the function print board.

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OK, now run your code.

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I'm going to pick the spot zero zero.

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And check it at.

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The function excuser return to my spot is an array of two integers.

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And we're using each integer to index the board and update the first element at Rosero.

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After updating the array, we're reprinting it.

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Now I'm going to update the third element of Roe to euro to index two, and everything works perfectly.

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I'll choose the first element from one zero one zero.

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The third element in row zero zero two and everything works well, OK, we're looking good so far.

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And you know what, I'm going to rerun the code.

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There is one thing I forgot to address, and that is the fact that the user can override a previous

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spot.

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Let me actually demonstrate that.

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If I pick a spot to zero, players should not be allowed to take that spot.

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But it does happen and we need to come up with a strategy to prevent this.

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If we turn back the task for there was still one more thing we had to do inside the function, and that

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was to check if the spot is taken.

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If so, let the user choose again.

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Conveniently, the function receives the board as a parameter so we can use a while loop and I can keep

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asking the user to pick a new spot if the one that they choose is taken.

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So while the spot that they choose.

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Is already equal to X.

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Or.

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If it's already equal to oh.

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Then we're going to print.

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Spot taken.

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Try again.

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It's important that we use print, not print line, because once again, we need the user to enter his

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enter beside the prompts and first we pick up the row, row is equal to scan to an extent.

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And then we'll pick up the Cullom.

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And I believe that wraps up part two.

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Because we're officially done tasks three, four and five.

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Let's run the code.

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I'm going to pick up some random spots.

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OK, good.

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Now I'm going to pick a spot that's already taken.

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It stops me from doing so, and it's going to keep stopping me until I choose one that isn't taken.

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Purrfect.

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What's happening is once the user picks a spot that isn't taken, the while loop breaks, it returns

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the spot in the form of an array and we're using the spot to index the board and update it with the

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appropriate symbol.

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Now, I'd like to show you that there are always so many ways to write code that achieves the exact

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same output, we know that the underscore represents a free spot.

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So instead of this big logical comparison, I can just check if the spot the player chooses is not free.

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Then keep asking them to pick another one.

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This code should achieve the exact same output.

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Once again, I'll pick random spots.

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OK, good, now pick a spot that's already taken, it stops me from doing so and like before it's going

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to keep stopping me until I choose one that isn't taken.

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Beautiful.

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Our game is really coming together.

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I'll see you in part three.