Homework03

.github/workflows/cs102.yml

@@ -7,10 +7,10 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v2
-    - name: Set up Python 3.8.6
+    - name: Set up Python 3.10.7
       uses: actions/setup-python@v2
       with:
-        python-version: '3.8.6'
+        python-version: '3.10.7'
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip

homework02/sudoku.py

@@ -1,11 +1,12 @@
 import pathlib
+import random
 import typing as tp
 
 T = tp.TypeVar("T")
 
 
 def read_sudoku(path: tp.Union[str, pathlib.Path]) -> tp.List[tp.List[str]]:
-    """ Прочитать Судоку из указанного файла """
+    """Прочитать Судоку из указанного файла"""
     path = pathlib.Path(path)
     with path.open() as f:
         puzzle = f.read()
@@ -19,7 +20,7 @@ def create_grid(puzzle: str) -> tp.List[tp.List[str]]:
 
 
 def display(grid: tp.List[tp.List[str]]) -> None:
-    """Вывод Судоку """
+    """Вывод Судоку"""
     width = 2
     line = "+".join(["-" * (width * 3)] * 3)
     for row in range(9):
@@ -42,7 +43,16 @@ def group(values: tp.List[T], n: int) -> tp.List[tp.List[T]]:
     >>> group([1,2,3,4,5,6,7,8,9], 3)
     [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
     """
-    pass
+    t: tp.List[T] = []
+    res = []
+    length = len(values)
+    for i in range(length):
+        if i % n == 0 and i != 0:
+            res.append(t)
+            t = []
+        t.append(values[i])
+    res.append(t)
+    return res
 
 
 def get_row(grid: tp.List[tp.List[str]], pos: tp.Tuple[int, int]) -> tp.List[str]:
@@ -55,7 +65,7 @@ def get_row(grid: tp.List[tp.List[str]], pos: tp.Tuple[int, int]) -> tp.List[str
     >>> get_row([['1', '2', '3'], ['4', '5', '6'], ['.', '8', '9']], (2, 0))
     ['.', '8', '9']
     """
-    pass
+    return grid[pos[0]]
 
 
 def get_col(grid: tp.List[tp.List[str]], pos: tp.Tuple[int, int]) -> tp.List[str]:
@@ -68,7 +78,10 @@ def get_col(grid: tp.List[tp.List[str]], pos: tp.Tuple[int, int]) -> tp.List[str
     >>> get_col([['1', '2', '3'], ['4', '5', '6'], ['.', '8', '9']], (0, 2))
     ['3', '6', '9']
     """
-    pass
+    res = []
+    for arr in grid:
+        res.append(arr[pos[1]])
+    return res
 
 
 def get_block(grid: tp.List[tp.List[str]], pos: tp.Tuple[int, int]) -> tp.List[str]:
@@ -82,10 +95,16 @@ def get_block(grid: tp.List[tp.List[str]], pos: tp.Tuple[int, int]) -> tp.List[s
     >>> get_block(grid, (8, 8))
     ['2', '8', '.', '.', '.', '5', '.', '7', '9']
     """
-    pass
+    res = []
+    r = pos[0] // 3 * 3
+    c = pos[1] // 3 * 3
+    for i in range(r, r + 3):
+        for j in range(c, c + 3):
+            res.append(grid[i][j])
+    return res
 
 
-def find_empty_positions(grid: tp.List[tp.List[str]]) -> tp.Optional[tp.Tuple[int, int]]:
+def find_empty_positions(grid: tp.List[tp.List[str]]) -> tp.Tuple[int, int]:
     """Найти первую свободную позицию в пазле
 
     >>> find_empty_positions([['1', '2', '.'], ['4', '5', '6'], ['7', '8', '9']])
@@ -95,7 +114,13 @@ def find_empty_positions(grid: tp.List[tp.List[str]]) -> tp.Optional[tp.Tuple[in
     >>> find_empty_positions([['1', '2', '3'], ['4', '5', '6'], ['.', '8', '9']])
     (2, 0)
     """
-    pass
+    if grid != 0:
+        for i in range(len(grid)):
+            for j in range(len(grid[i])):
+                if not grid[i][j].isdigit():
+                    r, c = i, j
+                    return r, c
+    return -1, -1
 
 
 def find_possible_values(grid: tp.List[tp.List[str]], pos: tp.Tuple[int, int]) -> tp.Set[str]:
@@ -109,11 +134,20 @@ def find_possible_values(grid: tp.List[tp.List[str]], pos: tp.Tuple[int, int]) -
     >>> values == {'2', '5', '9'}
     True
     """
-    pass
+    res = []
+    for arr in range(1, 10):
+        s = str(arr)
+        if (
+            s not in get_block(grid, pos)
+            and s not in get_col(grid, pos)
+            and s not in get_row(grid, pos)
+        ):
+            res.append(s)
+    return set(res)
 
 
 def solve(grid: tp.List[tp.List[str]]) -> tp.Optional[tp.List[tp.List[str]]]:
-    """ Решение пазла, заданного в grid """
+    """Решение пазла, заданного в grid"""
     """ Как решать Судоку?
         1. Найти свободную позицию
         2. Найти все возможные значения, которые могут находиться на этой позиции
@@ -125,13 +159,36 @@ def solve(grid: tp.List[tp.List[str]]) -> tp.Optional[tp.List[tp.List[str]]]:
     >>> solve(grid)
     [['5', '3', '4', '6', '7', '8', '9', '1', '2'], ['6', '7', '2', '1', '9', '5', '3', '4', '8'], ['1', '9', '8', '3', '4', '2', '5', '6', '7'], ['8', '5', '9', '7', '6', '1', '4', '2', '3'], ['4', '2', '6', '8', '5', '3', '7', '9', '1'], ['7', '1', '3', '9', '2', '4', '8', '5', '6'], ['9', '6', '1', '5', '3', '7', '2', '8', '4'], ['2', '8', '7', '4', '1', '9', '6', '3', '5'], ['3', '4', '5', '2', '8', '6', '1', '7', '9']]
     """
-    pass
+    empty = find_empty_positions(grid)  # type: tp.Tuple[int, int]
+    if empty[0] < 0:
+        return grid
+    possible = find_possible_values(grid, empty)  # type: tp.Set[str]
+    if not possible:
+        return None
+    for i in possible:
+        grid[empty[0]][empty[1]] = i
+        if solve(grid):
+            return grid
+        grid[empty[0]][empty[1]] = "."
+    return None
 
 
 def check_solution(solution: tp.List[tp.List[str]]) -> bool:
-    """ Если решение solution верно, то вернуть True, в противном случае False """
+    """Если решение solution верно, то вернуть True, в противном случае False"""
     # TODO: Add doctests with bad puzzles
-    pass
+    g = solution
+    for i in range(9):
+        if len(get_row(g, (i, 0))) != len(set(get_row(g, (i, 0)))) or len(
+            get_col(g, (0, i))
+        ) != len(set(get_col(g, (0, i)))):
+            return False
+        if i == 0 or i == 3 or i == 6:
+            for j in range(0, 9, 3):
+                if len(get_block(g, (i, j))) != len(set(get_block(g, (i, j)))):
+                    return False
+        if "." in g[i]:
+            return False
+    return True
 
 
 def generate_sudoku(N: int) -> tp.List[tp.List[str]]:
@@ -156,7 +213,15 @@ def generate_sudoku(N: int) -> tp.List[tp.List[str]]:
     >>> check_solution(solution)
     True
     """
-    pass
+    grid = [["."] * 9 for _ in range(9)]
+    solve(grid)
+    count, N = 0, min(81, N)
+    while count < 81 - N:
+        i, j = random.randint(0, 8), random.randint(0, 8)
+        if grid[i][j] != ".":
+            grid[i][j] = "."
+            count += 1
+    return grid
 
 
 if __name__ == "__main__":