Add own bitarray and Miller-Rabin primality test.

python/lib_bitarray.py

@@ -0,0 +1,39 @@
+class Bitarray:
+    def __init__(self, num_bits):
+        self.word_size = 32
+        self.word_mask = 2**self.word_size - 1
+        num_words = num_bits // self.word_size
+        if num_bits % self.word_size != 0:
+            num_words += 1
+        self.num_bits = num_bits
+        self.num_words = num_words
+        self.array = [0] * num_words
+
+    def setall(self, target: bool):
+        if target:
+            self.array = [self.word_mask] * self.num_words
+        else:
+            self.array = [0] * self.num_words
+
+    def set(self, bit, target: bool):
+        assert(bit < self.num_bits)
+        word_index = bit // self.word_size
+        bit_index = bit % self.word_size
+        value = self.array[word_index]
+        if target:
+            value = (value | (1 << bit_index))
+        else:
+            value = (value & (~(1 << bit_index)))
+        self.array[word_index] = value
+
+    def get(self, bit) -> bool:
+        assert(bit < self.num_bits)
+        word_index = bit // self.word_size
+        bit_index = bit % self.word_size
+        return bool(self.array[word_index] & (1 << bit_index))
+
+    def __getitem__(self, bit: int) -> bool:
+        return self.get(bit)
+
+    def __setitem__(self, bit: int, value: bool):
+        self.set(bit, value)