#! /usr/bin/lua

-- by Michael Anderson at
-- https://stackoverflow.com/questions/8722620/comparing-two-index-tables-by-index-value-in-lua
-- modified by Roger
function recursive_compare(t1,t2)
  -- Use usual comparison first.
  if t1==t2 then return true end
  -- We only support non-default behavior for tables
  if (type(t1)~="table") then return false end
  -- They better have the same metatables
  local mt1 = getmetatable(t1)
  local mt2 = getmetatable(t2)
  if( not recursive_compare(mt1,mt2) ) then return false end
  -- Build list of all keys
  local kk = {}
  for k1, _ in pairs(t1) do
     kk[k1] = true
  end
  for k2, _ in pairs(t2) do
     kk[k2] = true
  end
  -- Check each key that exists in at least one table
  for _, k in ipairs(kk) do
     if (not recursive_compare(t1[k], t2[k])) then
        return false
     end
  end
  return true
end

function is_prime(candidate)
   if candidate<2 then
      return false
   elseif candidate==2 then
      return true
   elseif candidate==3 then
      return true
   elseif candidate % 2 == 0 then
      return false
   elseif candidate % 3 == 0 then
      return false
   end
   local anchor=0
   local limit=math.floor(math.sqrt(candidate))
   while true do
      anchor = anchor + 6
      for t = anchor-1,anchor+1,2 do
         if t > limit then
            return true
         end
         if candidate % t == 0 then
            return false
         end
      end
   end
end

function binaryprefix(a)
   local out = {}
   local n = 0
   for _, x in ipairs(a) do
      n = n * 2
      if x == 1 then
         n = n + 1
      end
      table.insert(out, is_prime(n))
   end
   return out
end

if recursive_compare(binaryprefix({1, 0, 1}), {false, true, true}) then
  io.write("Pass")
else
  io.write("FAIL")
end
io.write(" ")

if recursive_compare(binaryprefix({1, 1, 0}), {false, true, false}) then
  io.write("Pass")
else
  io.write("FAIL")
end
io.write(" ")

if recursive_compare(binaryprefix({1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 0, 1}), {false, true, true, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, true}) then
  io.write("Pass")
else
  io.write("FAIL")
end
print("")