Data commit

Task/CUSIP/Lua/cusip.lua

@@ -0,0 +1,44 @@
+function checkDigit (cusip)
+  if #cusip ~= 8 then return false end
+
+  local sum, c, v, p = 0
+  for i = 1, 8 do
+    c = cusip:sub(i, i)
+    if c:match("%d") then
+      v = tonumber(c)
+    elseif c:match("%a") then
+      p = string.byte(c) - 55
+      v = p + 9
+    elseif c == "*" then
+      v = 36
+    elseif c == "@" then
+      v = 37
+    elseif c == "#" then
+      v = 38
+    end
+    if i % 2 == 0 then
+      v = v * 2
+    end
+
+    sum = sum + math.floor(v / 10) + v % 10
+  end
+
+  return tostring((10 - (sum % 10)) % 10)
+end
+
+local testCases = {
+  "037833100",
+  "17275R102",
+  "38259P508",
+  "594918104",
+  "68389X106",
+  "68389X105"
+}
+for _, CUSIP in pairs(testCases) do
+  io.write(CUSIP .. ": ")
+  if checkDigit(CUSIP:sub(1, 8)) == CUSIP:sub(9, 9) then
+    print("VALID")
+  else
+    print("INVALID")
+  end
+end