-- Rock-Paper-Scissors -- finished version.
-- Run with: lua projects/rock-paper-scissors/finished.lua

io.write("Choose rock, paper, or scissors: ")
local player = io.read()

-- the computer picks one of three at random, without a table
local roll = math.random(1, 3)
local computer
if roll == 1 then
    computer = "rock"
elseif roll == 2 then
    computer = "paper"
else
    computer = "scissors"
end

print("The computer chose " .. computer .. ".")

if player ~= "rock" and player ~= "paper" and player ~= "scissors" then
    print("That is not a valid choice.")
elseif player == computer then
    print("It is a tie!")
elseif (player == "rock" and computer == "scissors")
    or (player == "paper" and computer == "rock")
    or (player == "scissors" and computer == "paper") then
    print("You win!")
else
    print("You lose!")
end