local valid
local accounts = {
   ["username"] = "password",
   ["foo"] = "bar",
   ["xolbor"] = "roblox",
   ["anavrin"] = "nirvana"
}

term.clear()
term.setCursorPos(1, 1)

print("Enter username")
write("> ")
local input_user = read()

print("Enter password")
write("> ")
local input_pass = read("*")

for valid_user, valid_pass in pairs(accounts) do
   if (input_user == valid_user and input_pass == valid_pass) then valid = true end
end

if valid then print("Access Granted") else print("Access Denied") end