Переписывание контрольной работы

src/control_test/task1.py

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+import random
+
+
+class Walker:
+    def __init__(self, events):
+        self.events = []  # events = [(event, probability)]
+        self.n = len(events)
+        self.probabil = [0] * self.n
+        self.alias = [0] * self.n
+
+        probs = []
+        sumprob = 0
+        for event, p in events:
+            if p < 0:
+                raise ValueError("вероятность должна быть положительна")
+            self.events.append(event)
+            probs.append(p)
+            sumprob += p
+
+        if sumprob != 1.0:
+            raise ValueError("сумма вероятностей должна быть = 1")
+
+        wal = [p * self.n for p in probs]
+
+        for i in range(self.n):
+            if wal[i] >= 1:
+                self.probabil[i] = 1
+                self.alias[i] = i
+            else:
+                self.prob[i] = wal[i]
+                self.alias[i] = (i + 1) % self.n
+
+    def get_random(self):
+        i = random.randint(0, self.n - 1)
+        if random.random() < self.probabil[i]:
+            return self.events[i]
+        else:
+            return self.events[self.alias[i]]

src/control_test/task2.py

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+def hamming_encode(bits):
+    result = ""
+    for i in range(0, len(bits), 4):
+        d = list(map(int, bits[i : i + 4]))
+        p1 = d[0] ^ d[1] ^ d[3]
+        p2 = d[0] ^ d[2] ^ d[3]
+        p3 = d[1] ^ d[2] ^ d[3]
+        result += f"{p1}{p2}{d[0]}{p3}{d[1]}{d[2]}{d[3]}"
+    return result
+
+
+def hamming_decode(bits):
+    bits = list(map(int, bits))
+    for i in range(0, len(bits), 7):
+        b = bits[i : i + 7]
+        s1 = b[0] ^ b[2] ^ b[4] ^ b[6]
+        s2 = b[1] ^ b[2] ^ b[5] ^ b[6]
+        s3 = b[3] ^ b[4] ^ b[5] ^ b[6]
+        error = s1 * 1 + s2 * 2 + s3 * 4
+        if error != 0:
+            return i + error
+    return -1

tests/test_control_task1.py

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+import pytest
+from src.control_test.task1 import Walker
+
+
+def test_negative():
+    with pytest.raises(ValueError):
+        Walker([("A", 0.5), ("B", -0.5)])
+
+
+def test_sum_not_one():
+    with pytest.raises(ValueError):
+        Walker([("A", 0.6), ("B", 0.3)])

tests/test_control_task2.py

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+import pytest
+from src.control_test.task2 import hamming_encode
+from src.control_test.task2 import hamming_decode
+
+
+def test_encode_decode():
+    bits = "10110011"
+    encoded = hamming_encode(bits)
+    assert hamming_decode(encoded) == -1