Hi!
I’m trying to learn how to code in codea. I’m reading an e-book named “Lua for beginners” and in chapter 10 it’s a code which is this:
while wins.a<n and wins.b<n do str=""
--toss coins until someone wins
--check this by looking for a match
while string.find(str,a)==nil and string.find(str,b)==nil do
--add a random letter
--math.random gives a random number 0-1 unless you specify a range if math.random()<.5 then str=str.."H" else str=str.."T" end
end
--see who won
if string.find(str,a)~=nil then wins.a=wins.a+1 else wins.b=wins.b+1 end
end
--return the number of wins for each player return wins.a,wins.b
end --end of function
When I’m writing “nil” in codea it will only make error. What can I use instead of nil?
@Pontus712 when you post code in the forums, put three tilde characters ~~~ at the top and bottom of the code, then it will display with proper line-endings and indentation.
@Pontus712 I added the 3 ~'s to your code above for you. Here is the complete code for the example you posted above. There was nothing wrong with the code, but it was hard copying the code and getting it to run. Some of the actual code ended up in the comments.
function setup()
myPattern = "TTH"
--Codea takes the opposite of your first letter
--plus the first two letters of your choice
if string.sub(myPattern,1,1)=="H" then
Codea="T"..string.sub(myPattern,2,3)
else
Codea="H"..string.sub(myPattern,1,2)
end
print("You chose",myPattern)
print("I chose",Codea)
you,me= PlayGame(myPattern,Codea,100)
print ("You won",you,"games")
print("I won",me,"games")
if you>me then
print("You won!")
else
print("I won!")
end
end
function PlayGame(a,b,n)
--initialise number of wins
--the a and b in here are not the same as the a and b passed in above local
wins={a=0,b=0}
--keep going until one of them wins
while wins.a<n and wins.b<n do
str=""
--toss coins until someone wins
--check this by looking for a match
while string.find(str,a)==nil and string.find(str,b)==nil do
--add a random letter
--math.random gives a random number 0-1 unless you specify a range
if math.random()<.5 then
str=str.."H"
else
str=str.."T"
end
end
--see who won
if string.find(str,a)~=nil then
wins.a=wins.a+1
else
wins.b=wins.b+1
end
end
--return the number of wins for each player
return wins.a,wins.b
end
@Pontus712, have a look at the documentation for questions like that. string.sub(pattern, start, end means get the chunk from the string between start and end
