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Data update

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This commit is contained in:
Ingy döt Net 2024-07-13 15:19:22 -07:00
parent 29a5eea0d4
commit 5c1bb7bfa9
2011 changed files with 35081 additions and 3229 deletions
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30
Task/N-queens-problem/Python/n-queens-problem-7.py
View file

@ -1,23 +1,23 @@
def queens(n):
a = list(range(n))
up = [True]*(2*n - 1)
down = [True]*(2*n - 1)
def sub(i):
if i == n:
yield tuple(a)
else:
def queens(n: int):
def sub(i: int):
if i < n:
for k in range(i, n):
j = a[k]
p = i + j
q = i - j + n - 1
if up[p] and down[q]:
up[p] = down[q] = False
if b[i + j] and c[i - j]:
a[i], a[k] = a[k], a[i]
b[i + j] = c[i - j] = False
yield from sub(i + 1)
up[p] = down[q] = True
b[i + j] = c[i - j] = True
a[i], a[k] = a[k], a[i]
else:
yield a
a = list(range(n))
b = [True] * (2 * n - 1)
c = [True] * (2 * n - 1)
yield from sub(0)
#Count solutions for n=8:
sum(1 for p in queens(8))
sum(1 for p in queens(8)) # count solutions
92

38
Task/N-queens-problem/Python/n-queens-problem-8.py
View file

@ -1,31 +1,29 @@
def queens_lex(n):
a = list(range(n))
up = [True]*(2*n - 1)
down = [True]*(2*n - 1)
def sub(i):
if i == n:
yield tuple(a)
else:
def queens_lex(n: int):
def sub(i: int):
if i < n:
for k in range(i, n):
j = a[k]
a[i], a[k] = a[k], a[i]
j = a[i]
p = i + j
q = i - j + n - 1
if up[p] and down[q]:
up[p] = down[q] = False
if b[i + j] and c[i - j]:
b[i + j] = c[i - j] = False
yield from sub(i + 1)
up[p] = down[q] = True
x = a[i]
for k in range(i + 1, n):
a[k - 1] = a[k]
a[n - 1] = x
b[i + j] = c[i - j] = True
a[i:(n - 1)], a[n - 1] = a[(i + 1):n], a[i]
else:
yield a
a = list(range(n))
b = [True] * (2 * n - 1)
c = [True] * (2 * n - 1)
yield from sub(0)
next(queens(31))
(0, 2, 4, 1, 3, 8, 10, 12, 14, 6, 17, 21, 26, 28, 25, 27, 24, 30, 7, 5, 29, 15, 13, 11, 9, 18, 22, 19, 23, 16, 20)
[0, 2, 4, 1, 3, 8, 10, 12, 14, 6, 17, 21, 26, 28, 25, 27, 24, 30, 7, 5, 29, 15, 13, 11, 9, 18, 22, 19, 23, 16, 20]
next(queens_lex(31))
(0, 2, 4, 1, 3, 8, 10, 12, 14, 5, 17, 22, 25, 27, 30, 24, 26, 29, 6, 16, 28, 13, 9, 7, 19, 11, 15, 18, 21, 23, 20)
[0, 2, 4, 1, 3, 8, 10, 12, 14, 5, 17, 22, 25, 27, 30, 24, 26, 29, 6, 16, 28, 13, 9, 7, 19, 11, 15, 18, 21, 23, 20]
#Compare to A065188
#1, 3, 5, 2, 4, 9, 11, 13, 15, 6, 8, 19, 7, 22, 10, 25, 27, 29, 31, 12, 14, 35, 37, ...