Advanced password program bug

I made an advanced password program with tries and auto-lock. But I have a question : Each time it I "voluntary" make a mistake, it has a bug while counting and I can't set it to 0 every time :(/>. It says word by word : password:21: attempt to call arithmetic __add on nil and number

• local password = "Password" – Password
local side = "left" – Side to send the redstone signal
local time = 5 – Activation time for the signal
local totalTry = 5 – Total tries before self-locking
while true do
term.clear()
local try = try
print("Password : ")
local input = read("*")
if input == password then
term.clear()
print("Password correct !")
rs.setOutput(side, true)
local try = 0
os.sleep(time)
rs.setOutput(side, false)
else
term.clear()
print("Wrong password !")
local try = try+1
if try == totalTry then
print("Computer locked for 60 seconds !")
os.sleep(60)
else
term.write("Essaie restante : ")
term.write(totalTry-try) – The error says to be here !
term.write(" !")
end
os.sleep(2)
end
end

First things first, if you paste code on the forums, please use indentations and place the code in between the CODE /CODE brackets. You don't have to declare a local variable twice. You declared the variable try to be local in the if-statement. That's why it doesn't exist after the if-statement. Remove the local:

term.clear()
print("Wrong password!")
try = try + 1

Just so you know a little more about local variables

local str = "bar"
if str then
    local str = "foo"
    print( str )
end
print( str )

The code above would output

foo
bar

because when first declaring the local variable str to bar it's local to the program, while the second time it's local it's only used in the if statement

Thank you and I didn't know, when I posted it, it auto-formed it :3 sorry I will fix it for the next time

I will repost the code just to be clear (and I updated it a bit :3) :

local password = "Lancelot" -- Mot de Passe
local side = "left" -- Coter åA0 envoyer le signal
local time = 5 -- Temps d'activation du signal
local totalTry = 5 -- Essaie rater avant de se lock.
-- Don't touch to anything here unless you are crazy !--

while true do
local try = try
term.clear()
term.setCursorPos(1,1)
write("Mot de passe : ")
local input = read("*")
if input == password then
  term.clear()
  term.setCursorPos(1,1)
  print("Mot de passe correcte !")
  rs.setOutput(side, true)
  try = 0
  os.sleep(time)
  rs.setOutput(side, false)
else
  term.clear()
  term.setCursorPos(1,1)
  print("Mot de passe invalide !")
  try = try+1
   if try >= totalTry then
    print("Ordinateur bloquer pendant 60 secondes !")
    os.sleep(60)
    try = 0
   else
    term.write("Essaie restante : ")
    term.write(totalTry-try)
    term.write(" !")
   end
  os.sleep(2)
end
end

Thank you again just fixed it and it works fine !