Обновить u7/hash_table.py

2026-10-30 01:20:20 +00:00 · 2026-10-30 01:20:20 +00:00 · 2dc1599774
commit 2dc1599774
parent 7f9d5036d8
1 changed files with 104 additions and 0 deletions
--- a/u7/hash_table.py
+++ b/u7/hash_table.py
@ -0,0 +1,104 @@
+class HashTable:
+    _DELETED = object()
+    def __init__(self, capacity=10):
+        if type(capacity) != int:
+            raise TypeError("Capacity must be an integer")
+        if capacity <= 0:
+            raise ValueError("Capacity must be positive")
+        self._capacity = capacity
+        self._table = [None] * capacity
+        self._size = 0
+    @property
+    def capacity(self):
+        return self._capacity
+    def hash(self, key):
+        if type(key) != str:
+            raise TypeError
+        h = 0
+        for char in key:
+            h = (31 * h + ord(char)) % self.capacity
+        return h
+    def probe(self, key):
+        if type(key) != str:
+            raise TypeError
+        start = self.hash(key)
+        deleted = None
+        for i in range(self.capacity):
+            index = (start + i) % self.capacity
+            item = self._table[index]
+            if item is None:
+                if deleted is not None:
+                    return deleted
+                return index
+            if item is self._DELETED:
+                if deleted is None:
+                    deleted = index
+            elif item[0] == key:
+                return index
+        if deleted is not None:
+            return deleted
+        raise RuntimeError
+    def __setitem__(self, key, value):
+        if type(key) != str:
+            raise TypeError
+        try:
+            index = self.probe(key)
+            item = self._table[index]
+            if item is not None and item is not self._DELETED:
+                if item[0] == key:
+                    self._table[index] = (key, value)
+                    return
+        except RuntimeError:
+            pass
+        if (self._size + 1) / self.capacity > 0.7:
+            old_table = self._table
+            self._capacity = self._capacity * 2
+            self._table = [None] * self.capacity
+            self._size = 0
+            for item in old_table:
+                if item is not None and item is not self._DELETED:
+                    index = self.probe(item[0])
+                    self._table[index] = item
+                    self._size += 1
+        index = self.probe(key)
+        self._table[index] = (key, value)
+        self._size += 1
+    def __getitem__(self, key):
+        if type(key) != str:
+            raise TypeError
+        index = self.probe(key)
+        item = self._table[index]
+        if item is None or item is self._DELETED:
+            raise KeyError(key)
+        return item[1]
+    def __delitem__(self, key):
+        if type(key) != str:
+            raise TypeError
+        index = self.probe(key)
+        item = self._table[index]
+        if item is None or item is self._DELETED:
+            raise KeyError(key)
+        self._table[index] = self._DELETED
+        self._size -= 1
+    def __contains__(self, key):
+        if type(key) != str:
+            raise TypeError
+        try:
+            index = self.probe(key)
+            item = self._table[index]
+            if item is not None and item is not self._DELETED:
+                if item[0] == key:
+                    return True
+            return False
+        except RuntimeError:
+            return False
+    def __len__(self):
+        return self._size
+    def __iter__(self):
+        keys = []
+        for item in self._table:
+            if item is not None and item is not self._DELETED:
+                keys.append(item[0])
+        return iter(keys)
+    def load_factor(self):
+        return self._size / self.capacity