N-queens problem: Difference between revisions
m
→Python: Backtracking on permutations: Restored the original look
m (→Python: Backtracking on permutations: Minor editing) |
m (→Python: Backtracking on permutations: Restored the original look) |
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Line 12,865:
<syntaxhighlight lang="python">def queens(n: int):
def
if i < n:
for k in range(i, n):
if b[i + j] and c[i - j]:
a[i], a[k] =
b[i + j] = c[i - j] = False
yield from
b[i + j] = c[i - j] = True
a[i], a[k] =
else:
yield a
Line 12,881:
b = [True] * (2 * n - 1)
c = [True] * (2 * n - 1)
yield from
Line 12,893:
<syntaxhighlight lang="python">def queens_lex(n: int):
def
if i < n:
for k in range(i, n):
a[i], a[k] =
if b[i + j] and c[i - j]:
b[i + j] = c[i - j] = False
yield from
b[i + j] = c[i - j] = True
a[i:(n - 1)], a[n - 1] = a[(i + 1):n], a[i]
Line 12,909:
b = [True] * (2 * n - 1)
c = [True] * (2 * n - 1)
yield from
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