Merge remote-tracking branch 'upstream/master'

1 files changed, 38 insertions, 0 deletions

diff --git a/challenge-195/deadmarshal/lua/ch-2.lua b/challenge-195/deadmarshal/lua/ch-2.lua
new file mode 100644
index 0000000000..94a2ee7c4a
--- /dev/null
+++ b/challenge-195/deadmarshal/lua/ch-2.lua
@@ -0,0 +1,38 @@
+#!/usr/bin/env lua
+-- luarocks install stdlib
+local std = require'std'
+
+local function is_uniq(t)
+  for i=1, #t do
+    for j=i+1, #t do
+      if t[i] == t[j] then return false end
+    end
+  end
+  return true
+end
+
+local function most_frequent_even(t)
+  if #std.functional.filter(std.functional.lambda('|e| e % 2 ~= 0'),
+			    std.elems,t) == #t then
+    return -1
+  end
+  t = std.functional.filter(std.functional.lambda('|e| e % 2 == 0'),
+			    std.elems,t)
+  local hash = {}
+  setmetatable(hash,{__index = function(t,k) return 0 end})
+  for i=1,#t do hash[t[i]] = hash[t[i]] + 1 end
+  if is_uniq(std.table.values(hash)) then
+    return math.min(std.table.unpack(std.table.keys(hash)))
+  end
+  local sorted = std.table.okeys(hash)
+  for i=1,#sorted-1 do
+    if hash[sorted[i]] == hash[sorted[i+1]] then
+      return sorted[i]
+    end
+  end
+end
+
+print(most_frequent_even({1,1,2,6,2}))
+print(most_frequent_even({1,3,5,7}))
+print(most_frequent_even({6,4,4,6,1}))
+