Need some help

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Summary:

Program has some issues

Need some help

Fred511 20 Aug 2010 06:47

I'm trying to make a single player Battleship game, but when I got to the section where you select the orientation of the ship (basically ships are placed by selecting a coordinate then whether it faces left, right, etc) and I'm having alot of trouble, for some reason it doesn't want to loop, it runs once and says Done

Here's the code

Lbl C
getKey->K
If K=24 Then
1->C (C is orientation of ship, 1 being left, 2 being up, 3 right, etc)
Goto B
Else
If K=25 Then
2->C
Goto B
Else
If K=26 Then
3->C
Goto B
Else
If K=34
4->C
Goto B
Else
Goto C
Lbl B

Re: Need some help

Weregoose 20 Aug 2010 11:10

Warning: I write this after spending a night without sleep.

Learn how to use End. (Also, While and Repeat.) Note that you can omit Then and End if you only need to execute one statement after the condition.

And never Goto out of a conditional block – the calculator is left wondering where the End is that it was supposed to reach, which, done repetitiously, will cause the program to halt with a memory error.

Something like this suffices:

Repeat K=24 or K=25 or K=26 or K=34
getKey→K
If K=24
1→C
If K=25
2→C
If K=26
3→C
If K=34
4→C
End

Actually, this will work, too:

Repeat Ans>0 and Ans<5
getKey
int(5Ans-5Ans²/61-71→C
End

Or this:

Repeat Ans<5
5-sum(cumSum(getKey={24,25,26,34→C
End

My advice: start again smaller. Do a sum of digits routine, or script a robot through a constructed maze. Battleship is an intermediate project.

I feel it is also pertinent to criticize the logic of your routine. When a number gets stored to K (we'll say 24), the first condition will hold true, and the other three won't; there's no reason to try to skip over them with Goto. The interpreter always analyzes everything linearly – let it store to C and proceed to test the other statements as it goes downward. If they're false, then no action will be taken. One condition need not always be written as an opposition to the other.

What's causing the issue is that you're initiating a multi-line conditional block with the Then command, but not closing any of them with an End command, which is what the interpreter must read before terminating a condition. Your nesting of these means that you'll have to place an End for each of them at the bottom. You could also write them separately as above, or more explicitly as below:

Repeat K=24 or K=25 or K=26 or K=34
getKey→K
If K=24
Then
1→C
End
If K=25
Then
2→C
End
If K=26
Then
3→C
End
If K=34
Then
4→C
End
End

In this case, the outermost End corresponds to the condition of the Repeat.

Looking at the above code, you can probably take the inside four conditions out of the loop altogether.

Last edited on 20 Aug 2010 12:11 by Weregoose Show more

Re: Need some help

Fred511 20 Aug 2010 14:19

Thanks, I've been reading alot on this site, but that's about as far as my programming experience goes (besides just messing around with quadratic formula programs and the like)

Re: Need some help

Yatzy 20 Aug 2010 15:14

May I ask exactly how you derived this code, Weregoose :O?

int(5Ans-5Ans²/61-71→C

Re: Need some help

Weregoose 20 Aug 2010 20:25

The 26–34 gap exceeds the span of the first three values, so any slope-intercept pair that produces 26'–25'=34'–26' would upset the 25'–24' foremost, making all linear equations non-amenable to the isomorphism attained by the given second-order function. As for its build, it was manually extrapolated from a quadratic regression. What's to tell?

Last edited on 20 Aug 2010 20:26 by Weregoose Show more

Re: Need some help

Fred511 27 Aug 2010 06:47

ok, I have a new problem, this time it's a bit more complex. The issue isn't so much of getting it to work, because it works fine, but an issue of space.

I got through the player ship placement and drawing section, but then i started work on the computer's ships and after doing the first ship things started getting really, really long. Here's the code for the first and second ships, you'll see what I mean.

So I've arranged all the values into lists called "L BSHIP, L CARIR, L DSRYR, L SUB, L PTB" whose values are arranged {X1, X2, X3,X4, X5, Y1, Y2, etc}

randInt (0,9)-> A X Coordinate on 10x10 grid starting at 0
randInt (0,9)-> B Y Coordinate
randInt (1,2)-> C Whether it's oriented up or down
If A>8 and C=1:Then So that the ships don't go off grid
A->L BSHIP (4)
A-1 -> L BSHIP (3)
A-2 -> L BSHIP (2)
A-3 -> L BSHIP (1)
End
If A<2 and C=1:Then
A-> L BSHIP (1)
A+1 -> L BSHIP (2)
A+2 -> L BSHIP (3)
A+3 -> L BSHIP (4)
End
If A=/<8 and A=/>2 and C= 1:Then
A -> L BSHIP (3)
A+1 -> L BSHIP (4)
A-1 -> L BSHIP (2)
A-2 -> L BSHIP (1)
End

This is repeated substituting B for A and making the list value 4+ the value listed here and making the conditionals require C=2 instead of C=1

If C=1:Then
For (E,1,4)
B-> L BSHIP (E+4) So that when it's oriented on the X-Axis the Y values are all the same and vice versa
End:End
If C=2: Then
For (E,1,4)
A-> L BSHIP (E)
End:End

Here's the fun part, the second ship- everything works perfectly fine btw, I just need a slimmer way of managing this next bit of code

1->D
randInt(1,2)->C
Repeat D=5
randInt (0,9)-> A
For (E,1,4)
If A<8 and A>1:Then
If A= L BSHIP (E) xor A+1= L BSHIP (E) xor A+2= L BSHIP (E) xor A-1= L BSHIP(E) xor A-2= L BSHIP (E)
Then
1-> D Tells it to select another random integer and run this check again
Else
5->D
End:End
If A>7:Then
If A= L BSHIP (E) xor A-1= L BSHIP (E) xor A-2= L BSHIP (E) xor A-3= L BSHIP(E) xor A-4= L BSHIP (E)
Then
1->D
Else
5->D
End:End
If A<2:Then
If A= L BSHIP (E) xor A+1= L BSHIP (E) xor A+2= L BSHIP (E) xor A+3= L BSHIP(E) xor A+4= L BSHIP (E)
Then
1->D
Else
5-> D
End:End
End
1->D

Now it selects the Y Coordinate

Repeat D=5
randInt (0,9)-> B
For (E,1,4)
If B<8 and B>1:Then
If B= L BSHIP (E+4) xor B+1= L BSHIP (E+4) xor B+2= L BSHIP (E+4) xor B-1= L BSHIP(E+4) xor B-2= L BSHIP (E+4)
Then
1-> D
Else
5->D
End:End
If B>7:Then
If B= L BSHIP (E+4) xor B-3= L BSHIP (E+4) xor B-4= L BSHIP (E+4) xor B-1= L BSHIP(E+4) xor B-2= L BSHIP (E+4)
Then
1->D
Else
5->D
End:End
If B<2:Then
If B= L BSHIP (E+4) xor B+1= L BSHIP (E+4) xor B+2= L BSHIP (E+4) xor B+3= L BSHIP(E+4) xor B+4= L BSHIP (E+4)
Then
1->D
Else
5-> D
End:End
End

Now it sets the values of L CARIR

If A>7 and C=1:Then
A-> L CARIR (5)
A-1-> L CARIR (4)…..
A-4-> L CARIR (1)
End
If A<2 and C=1:Then
A-> L CARIR (1)
A+1-> L CARIR (2)……
A+4-> L CARIR (5)
End
If A<8 and A>1 and C=1:Then
A-> L CARIR (3)
A+1/2-> L CARIR (4/5)
A-1/2-> L CARIR (2/1)
End

Repeats for B, exactly the same except L CARIR is values between 6-10

For (E,1,5)
If D=1
B->L CARIR (E+5)
If D=2
A->L CARIR (E)
End

Hence my problem. The secton where it actually selects the coordinate is the main problem, as when I add third, fourth and fifth ships I will have to check each and every value with xor conditionals, which will be a real pain in the ass and take up loads of memory, and make the code difficult to debug. Any thoughts on how to do this with For loops, Repeats, whatever, would be greatly appreciated

Re: Need some help

burr 27 Aug 2010 15:23

This looks like a pretty challenging project — I'm sure you'll learn a lot :D

The biggest thing that stands out to me is the redundancy of your code: you are individually doing the same checks for all of the ships. Whenever you see that property in code, it should be a red flag. I realize you're just starting out in programming, but it is important to learn proper design. Your programs will not only be smaller and faster, but also have a certain elegance — the code looks nice, it is easy to read, and it is very compact.

I don't want to just give you code, but one easy change you could make is having the C variable alternate between the values of 0 and 1 instead of 1 and 2. This would allow you to do some optimization: every place where you use ∟BSHIP(E) and ∟BSHIP(E+4) would just be ∟BSHIP(E+4C). Does that make sense? Can you extrapolate that idea out to the bigger picture?