26 lines
779 B
Python
26 lines
779 B
Python
|
"""
|
||
|
|
Author: Wenru Dong
|
||
|
|
"""
|
||
|
|
|
||
|
|
from typing import List
|
||
|
|
|
||
|
|
def eight_queens() -> None:
|
||
|
|
solutions = []
|
||
|
|
|
||
|
|
def backtracking(queens_at_column: List[int], index_sums: List[int], index_diffs: List[int]) -> None:
|
||
|
|
row = len(queens_at_column)
|
||
|
|
if row == 8:
|
||
|
|
solutions.append(queens_at_column)
|
||
|
|
return
|
||
|
|
for col in range(8):
|
||
|
|
if col in queens_at_column or row + col in index_sums or row - col in index_diffs: continue
|
||
|
|
backtracking(queens_at_column + [col], index_sums + [row + col], index_diffs + [row - col])
|
||
|
|
|
||
|
|
backtracking([], [], [])
|
||
|
|
print(*(" " + " ".join("*" * i + "Q" + "*" * (8 - i - 1) + "\n" for i in solution) for solution in solutions), sep="\n")
|
||
|
|
|
||
|
|
|
||
|
|
if __name__ == "__main__":
|
||
|
|
|
||
|
|
eight_queens()
|