Merge pull request #822 from aconconi/25-chief-lua

25-chief-lua

25_Chief/lua/README.md

@@ -1,3 +1,24 @@
 Original source downloaded [from Vintage Basic](http://www.vintage-basic.net/games.html)
 
-Conversion to [Lua](https://www.lua.org/)
+Conversion to [Lua](https://www.lua.org/) by Alex Conconi
+
+---
+
+### Lua porting notes
+
+- I did not like the old Western movie language style in the game introduction
+and decided to tone it down, even if this deviates from the original BASIC
+version.
+
+- The `craps_game` function contains the main game logic: it
+  - prints the game credits and presents the intro question;
+  - asks for the end result and computes the original numer;
+  - calls `explain_solution` to print the various steps of the computation;
+  - presents the outro question and prints a `bolt` if necessary.
+
+- Added basic input validation to accept only valid integers for numeric input.
+
+- Minor formatting edits (lowercase, punctuation).
+
+- Any answer to a "yes or no" question is regarded as "yes" if the input line
+starts with 'y' or 'Y', else no.

25_Chief/lua/chief.lua

@@ -0,0 +1,121 @@
+--[[
+Chief
+
+From: BASIC Computer Games (1978)
+Edited by David H. Ahl
+
+    In the words of the program author, John Graham, “CHIEF is designed to
+    give people (mostly kids) practice in the four operations (addition,
+    multiplication, subtraction, and division).
+
+    It does this while giving people some fun. And then, if the people are
+    wrong, it shows them how they should have done it.
+
+    CHIEF was written by John Graham of Upper Brookville, New York.
+
+    
+Lua port by Alex Conconi, 2022.
+]]--
+
+
+--- Helper function for tabulating messages.
+local function space(n) return string.rep(" ", n) end
+
+
+--- Generates a multi-line string representing a lightning bolt
+local function bolt()
+    local bolt_lines = {}
+    for n = 29, 21, -1 do
+        table.insert(bolt_lines, space(n) .. "x x")
+    end
+    table.insert(bolt_lines, space(20) .. "x xxx")
+    table.insert(bolt_lines, space(19) .. "x   x")
+    table.insert(bolt_lines, space(18) .. "xx x")
+    for n = 19, 12, -1 do
+        table.insert(bolt_lines, space(n) .. "x x")
+    end
+    table.insert(bolt_lines, space(11) .. "xx")
+    table.insert(bolt_lines, space(10) .. "x")
+    table.insert(bolt_lines, space(9) .. "*\n")
+    table.insert(bolt_lines, string.rep("#", 25) .. "\n")
+    return table.concat(bolt_lines, "\n")
+end
+
+
+--- Print the prompt and read a yes/no answer from stdin.
+local function ask_yes_or_no(prompt)
+    io.stdout:write(prompt .. " ")
+    local answer = string.lower(io.stdin:read("*l"))
+    -- any line starting with a 'y' or 'Y' is considered a 'yes'
+    return answer:sub(1, 1) == "y"
+end
+
+
+--- Print the prompt and read a valid number from stdin.
+local function ask_number(prompt)
+    io.stdout:write(prompt .. " ")
+    while true do
+        local n = tonumber(io.stdin:read("*l"))
+        if n then
+            return n
+        else
+            print("Enter a valid number.")
+        end
+    end
+end
+
+
+--- Explain the solution to persuade the player.
+local function explain_solution()
+    local k = ask_number("What was your original number?")
+    -- For clarity we kept the same variable names of the original BASIC version
+    local f = k + 3
+    local g = f / 5
+    local h = g * 8
+    local i = h / 5 + 5
+    local j = i - 1
+    print("So you think you're so smart, eh?")
+    print("Now watch.")
+    print(k .. " plus 3 equals " .. f .. ". This divided by 5 equals " .. g .. ";")
+    print("this times 8 equals " .. h .. ". If we divide by 5 and add 5,")
+    print("we get " .. i .. ", which, minus 1, equals " .. j .. ".")
+end
+
+
+--- Main game function.
+local function chief_game()
+    --- Print game introduction and challenge
+    print(space(29) .. "Chief")
+    print(space(14) .. "Creative Computing  Morristown, New Jersey\n\n")
+    print("I am Chief Numbers Freek, the great math god.")
+    if not ask_yes_or_no("Are you ready to take the test you called me out for?") then
+        print("Shut up, wise tongue.")
+    end
+
+    -- Print how to obtain the end result.
+    print(" Take a number and add 3. Divide this number by 5 and")
+    print("multiply by 8. Divide by 5 and add the same. Subtract 1.")
+
+    -- Ask the result end and reverse calculate the original number.
+    local end_result = ask_number(" What do you have?")
+    local original_number = (end_result + 1 - 5) * 5 / 8 * 5 - 3
+
+    -- If it is an integer we do not want to print any zero decimals.
+    local int_part, dec_part = math.modf(original_number)
+    if dec_part == 0 then original_number = int_part end
+
+    -- If the player challenges the answer, print the explanation.
+    if not ask_yes_or_no("I bet your number was " .. original_number .. ". Am I right?") then
+        explain_solution()
+        -- If the player does not accept the explanation, zap them.
+        if not ask_yes_or_no("Now do you believe me?") then
+            print("YOU HAVE MADE ME MAD!!!")
+            print("THERE MUST BE A GREAT LIGHTNING BOLT!\n\n")
+            print(bolt())
+            print("I hope you believe me now, for your sake!!")
+        end
+    end
+end
+
+--- Run the game.
+chief_game()