Charakterbewegungen hinzugefügt, Deko hinzugefügt, Kochrezepte angepasst

mods/futil/util/selection.lua

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+local floor = math.floor
+local min = math.min
+local random = math.random
+
+local swap = futil.table.swap
+local default_cmp = futil.math.cmp
+
+futil.selection = {}
+
+local function partition5(t, left, right, cmp)
+	cmp = cmp or default_cmp
+	local i = left + 1
+	while i <= right do
+		local j = i
+		while j > left and cmp(t[j], t[j - 1]) do
+			swap(t, j - 1, j)
+			j = j - 1
+		end
+		i = i + 1
+	end
+	return floor((left + right) / 2)
+end
+
+local function partition(t, left, right, pivot_i, i, cmp)
+	cmp = cmp or default_cmp
+	local pivot_v = t[pivot_i]
+	swap(t, pivot_i, right)
+	local store_i = left
+	for j = left, right - 1 do
+		if cmp(t[j], pivot_v) then
+			swap(t, store_i, j)
+			store_i = store_i + 1
+		end
+	end
+	local store_i_eq = store_i
+	for j = store_i, right - 1 do
+		if t[j] == pivot_v then
+			swap(t, store_i_eq, j)
+			store_i_eq = store_i_eq + 1
+		end
+	end
+	swap(t, right, store_i_eq)
+	if i < store_i then
+		return store_i
+	elseif i <= store_i_eq then
+		return i
+	else
+		return store_i_eq
+	end
+end
+
+local function quickselect(t, left, right, i, pivot_alg, cmp)
+	cmp = cmp or default_cmp
+	while true do
+		if left == right then
+			return left
+		end
+		local pivot_i = partition(t, left, right, pivot_alg(t, left, right, cmp), i, cmp)
+		if i == pivot_i then
+			return i
+		elseif i < pivot_i then
+			right = pivot_i - 1
+		else
+			left = pivot_i + 1
+		end
+	end
+end
+
+futil.selection.quickselect = quickselect
+
+futil.selection.pivot = {}
+
+function futil.selection.pivot.random(t, left, right, cmp)
+	return random(left, right)
+end
+
+local function pivot_medians_of_medians(t, left, right, cmp)
+	cmp = cmp or default_cmp
+	if right - left < 5 then
+		return partition5(t, left, right, cmp)
+	end
+	for i = left, right, 5 do
+		local sub_right = min(i + 4, right)
+		local median5 = partition5(t, i, sub_right, cmp)
+		swap(t, median5, left + floor((i - left) / 5))
+	end
+	local mid = floor((right - left) / 10) + left + 1
+	return quickselect(t, left, left + floor((right - left) / 5), mid, pivot_medians_of_medians, cmp)
+end
+
+futil.selection.pivot.median_of_medians = pivot_medians_of_medians
+
+--[[
+make use of quickselect to munge a table:
+	median_index = math.floor(#t / 2)
+	after calling this,
+	t[1] through t[median_index - 1] will be the elements less than t[median_index]
+	t[median_index] will be the median (or element less-than-the-median for even length tables)
+	t[median_index + 1] through t[#t] will be the elements greater than t[median_index]
+pivot is a pivot algorithm, defaults to random selection
+cmp is a comparison function.
+returns median_index.
+]]
+function futil.selection.select(t, pivot_alg, cmp)
+	cmp = cmp or default_cmp
+	pivot_alg = pivot_alg or futil.selection.pivot.random
+	local median_index = math.floor(#t / 2)
+	return quickselect(t, 1, #t, median_index, pivot_alg, cmp)
+end