Data update

Task/Greatest-subsequential-sum/Lua/greatest-subsequential-sum.lua

@@ -8,7 +8,25 @@ function maxsub(ary, idx)
   end
   local v = maxsub(ary, idx + 1)
   if maxsum < sumt(v, 1, #v) then return v end
-  local ret = {}
-  for i = idx, last do ret[#ret+1] = ary[i] end
-  return ret
+  local ret, allNegative = {}, true
+  for i = idx, last do
+      ret[#ret+1] = ary[i]
+      if ret[#ret] >= 0 then allNegative = false end
+  end
+  return allNegative and {} or ret
 end
+
+local function test(s)
+    local msub = maxsub(s)
+    print("["..table.concat(s, " ").."] -> ["..table.concat(msub, " ").."] sum: "..sumt(msub, 1, #msub))
+end
+
+-- test cases from 11l
+test {-1, 2, -1}
+test {-1, 2, -1, 3, -1}
+test {-1, 1, 2, -5, -6}
+test {-1, -2, 3, 5, 6, -2, -1, 4, -4, 2, -1}
+
+-- additional test cases
+test {-1, -2, -1}
+test {}