8e1018fef7
* feat: repo map * chore: remove breakline * chore: remove spaces * fix: golang public method * feat: mentions for editing input
116 lines
2.3 KiB
Lua
116 lines
2.3 KiB
Lua
local LRUCache = {}
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LRUCache.__index = LRUCache
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function LRUCache:new(capacity)
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return setmetatable({
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capacity = capacity,
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cache = {},
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head = nil,
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tail = nil,
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size = 0,
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}, LRUCache)
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end
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-- Internal function: Move node to head (indicating most recently used)
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function LRUCache:_move_to_head(node)
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if self.head == node then return end
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-- Disconnect the node
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if node.prev then node.prev.next = node.next end
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if node.next then node.next.prev = node.prev end
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if self.tail == node then self.tail = node.prev end
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-- Insert the node at the head
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node.next = self.head
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node.prev = nil
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if self.head then self.head.prev = node end
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self.head = node
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if not self.tail then self.tail = node end
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end
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-- Get value from cache
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function LRUCache:get(key)
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local node = self.cache[key]
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if not node then return nil end
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self:_move_to_head(node)
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return node.value
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end
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-- Set value in cache
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function LRUCache:set(key, value)
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local node = self.cache[key]
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if node then
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node.value = value
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self:_move_to_head(node)
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else
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node = { key = key, value = value }
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self.cache[key] = node
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self.size = self.size + 1
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self:_move_to_head(node)
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if self.size > self.capacity then
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local tail_key = self.tail.key
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self.tail = self.tail.prev
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if self.tail then self.tail.next = nil end
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self.cache[tail_key] = nil
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self.size = self.size - 1
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end
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end
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end
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-- Remove specified cache entry
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function LRUCache:remove(key)
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local node = self.cache[key]
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if not node then return end
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if node.prev then
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node.prev.next = node.next
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else
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self.head = node.next
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end
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if node.next then
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node.next.prev = node.prev
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else
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self.tail = node.prev
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end
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self.cache[key] = nil
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self.size = self.size - 1
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end
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-- Get current size of cache
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function LRUCache:get_size() return self.size end
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-- Get capacity of cache
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function LRUCache:get_capacity() return self.capacity end
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-- Print current cache contents (for debugging)
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function LRUCache:print_cache()
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local node = self.head
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while node do
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print(node.key, node.value)
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node = node.next
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end
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end
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function LRUCache:keys()
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local keys = {}
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local node = self.head
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while node do
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table.insert(keys, node.key)
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node = node.next
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end
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return keys
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end
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return LRUCache
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