RosettaCodeData/Task/N-queens-problem/Python/n-queens-problem-4.py

20 lines
665 B
Python

BOARD_SIZE = 8
def under_attack(col, queens):
return col in queens or \
any(abs(col - x) == len(queens)-i for i,x in enumerate(queens))
def solve(n):
solutions = [[]]
for row in range(n):
solutions = (solution+[i+1]
for solution in solutions # first for clause is evaluated immediately,
# so "solutions" is correctly captured
for i in range(BOARD_SIZE)
if not under_attack(i+1, solution))
return solutions
answers = solve(BOARD_SIZE)
first_answer = next(answers)
print(list(enumerate(first_answer, start=1)))