Merge remote-tracking branch 'origin/master'

Author: Suyashd999

Diff for: backtracking/crossword_puzzle_solver.py

@@ -0,0 +1,132 @@
+# https://www.geeksforgeeks.org/solve-crossword-puzzle/
+
+
+def is_valid(
+    puzzle: list[list[str]], word: str, row: int, col: int, vertical: bool
+) -> bool:
+    """
+    Check if a word can be placed at the given position.
+
+    >>> puzzle = [
+    ...     ['', '', '', ''],
+    ...     ['', '', '', ''],
+    ...     ['', '', '', ''],
+    ...     ['', '', '', '']
+    ... ]
+    >>> is_valid(puzzle, 'word', 0, 0, True)
+    True
+    >>> puzzle = [
+    ...     ['', '', '', ''],
+    ...     ['', '', '', ''],
+    ...     ['', '', '', ''],
+    ...     ['', '', '', '']
+    ... ]
+    >>> is_valid(puzzle, 'word', 0, 0, False)
+    True
+    """
+    for i in range(len(word)):
+        if vertical:
+            if row + i >= len(puzzle) or puzzle[row + i][col] != "":
+                return False
+        else:
+            if col + i >= len(puzzle[0]) or puzzle[row][col + i] != "":
+                return False
+    return True
+
+
+def place_word(
+    puzzle: list[list[str]], word: str, row: int, col: int, vertical: bool
+) -> None:
+    """
+    Place a word at the given position.
+
+    >>> puzzle = [
+    ...     ['', '', '', ''],
+    ...     ['', '', '', ''],
+    ...     ['', '', '', ''],
+    ...     ['', '', '', '']
+    ... ]
+    >>> place_word(puzzle, 'word', 0, 0, True)
+    >>> puzzle
+    [['w', '', '', ''], ['o', '', '', ''], ['r', '', '', ''], ['d', '', '', '']]
+    """
+    for i, char in enumerate(word):
+        if vertical:
+            puzzle[row + i][col] = char
+        else:
+            puzzle[row][col + i] = char
+
+
+def remove_word(
+    puzzle: list[list[str]], word: str, row: int, col: int, vertical: bool
+) -> None:
+    """
+    Remove a word from the given position.
+
+    >>> puzzle = [
+    ...     ['w', '', '', ''],
+    ...     ['o', '', '', ''],
+    ...     ['r', '', '', ''],
+    ...     ['d', '', '', '']
+    ... ]
+    >>> remove_word(puzzle, 'word', 0, 0, True)
+    >>> puzzle
+    [['', '', '', ''], ['', '', '', ''], ['', '', '', ''], ['', '', '', '']]
+    """
+    for i in range(len(word)):
+        if vertical:
+            puzzle[row + i][col] = ""
+        else:
+            puzzle[row][col + i] = ""
+
+
+def solve_crossword(puzzle: list[list[str]], words: list[str]) -> bool:
+    """
+    Solve the crossword puzzle using backtracking.
+
+    >>> puzzle = [
+    ...     ['', '', '', ''],
+    ...     ['', '', '', ''],
+    ...     ['', '', '', ''],
+    ...     ['', '', '', '']
+    ... ]
+
+    >>> words = ['word', 'four', 'more', 'last']
+    >>> solve_crossword(puzzle, words)
+    True
+    >>> puzzle = [
+    ...     ['', '', '', ''],
+    ...     ['', '', '', ''],
+    ...     ['', '', '', ''],
+    ...     ['', '', '', '']
+    ... ]
+    >>> words = ['word', 'four', 'more', 'paragraphs']
+    >>> solve_crossword(puzzle, words)
+    False
+    """
+    for row in range(len(puzzle)):
+        for col in range(len(puzzle[0])):
+            if puzzle[row][col] == "":
+                for word in words:
+                    for vertical in [True, False]:
+                        if is_valid(puzzle, word, row, col, vertical):
+                            place_word(puzzle, word, row, col, vertical)
+                            words.remove(word)
+                            if solve_crossword(puzzle, words):
+                                return True
+                            words.append(word)
+                            remove_word(puzzle, word, row, col, vertical)
+                return False
+    return True
+
+
+if __name__ == "__main__":
+    PUZZLE = [[""] * 3 for _ in range(3)]
+    WORDS = ["cat", "dog", "car"]
+
+    if solve_crossword(PUZZLE, WORDS):
+        print("Solution found:")
+        for row in PUZZLE:
+            print(" ".join(row))
+    else:
+        print("No solution found:")

Diff for: conversions/ipv4_conversion.py

@@ -0,0 +1,85 @@
+# https://www.geeksforgeeks.org/convert-ip-address-to-integer-and-vice-versa/
+
+
+def ipv4_to_decimal(ipv4_address: str) -> int:
+    """
+    Convert an IPv4 address to its decimal representation.
+
+    Args:
+        ip_address: A string representing an IPv4 address (e.g., "192.168.0.1").
+
+    Returns:
+        int: The decimal representation of the IP address.
+
+    >>> ipv4_to_decimal("192.168.0.1")
+    3232235521
+    >>> ipv4_to_decimal("10.0.0.255")
+    167772415
+    >>> ipv4_to_decimal("10.0.255")
+    Traceback (most recent call last):
+        ...
+    ValueError: Invalid IPv4 address format
+    >>> ipv4_to_decimal("10.0.0.256")
+    Traceback (most recent call last):
+        ...
+    ValueError: Invalid IPv4 octet 256
+    """
+
+    octets = [int(octet) for octet in ipv4_address.split(".")]
+    if len(octets) != 4:
+        raise ValueError("Invalid IPv4 address format")
+
+    decimal_ipv4 = 0
+    for octet in octets:
+        if not 0 <= octet <= 255:
+            raise ValueError(f"Invalid IPv4 octet {octet}")  # noqa: EM102
+        decimal_ipv4 = (decimal_ipv4 << 8) + int(octet)
+
+    return decimal_ipv4
+
+
+def alt_ipv4_to_decimal(ipv4_address: str) -> int:
+    """
+    >>> alt_ipv4_to_decimal("192.168.0.1")
+    3232235521
+    >>> alt_ipv4_to_decimal("10.0.0.255")
+    167772415
+    """
+    return int("0x" + "".join(f"{int(i):02x}" for i in ipv4_address.split(".")), 16)
+
+
+def decimal_to_ipv4(decimal_ipv4: int) -> str:
+    """
+    Convert a decimal representation of an IP address to its IPv4 format.
+
+    Args:
+        decimal_ipv4: An integer representing the decimal IP address.
+
+    Returns:
+        The IPv4 representation of the decimal IP address.
+
+    >>> decimal_to_ipv4(3232235521)
+    '192.168.0.1'
+    >>> decimal_to_ipv4(167772415)
+    '10.0.0.255'
+    >>> decimal_to_ipv4(-1)
+    Traceback (most recent call last):
+        ...
+    ValueError: Invalid decimal IPv4 address
+    """
+
+    if not (0 <= decimal_ipv4 <= 4294967295):
+        raise ValueError("Invalid decimal IPv4 address")
+
+    ip_parts = []
+    for _ in range(4):
+        ip_parts.append(str(decimal_ipv4 & 255))
+        decimal_ipv4 >>= 8
+
+    return ".".join(reversed(ip_parts))
+
+
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod()