You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
31 lines
422 B
Python
31 lines
422 B
Python
import time
|
|
|
|
|
|
# T[i] += value
|
|
def add(t, i, value):
|
|
while i < len(t):
|
|
t[i] += value
|
|
i |= i + 1
|
|
|
|
|
|
# sum[0..i]
|
|
def sum(t, i):
|
|
res = 0
|
|
while i >= 0:
|
|
res += t[i]
|
|
i = (i & (i + 1)) - 1
|
|
return res
|
|
|
|
|
|
def test():
|
|
start = time.time()
|
|
n = 100000
|
|
t = [0] * n
|
|
for i in range(n):
|
|
add(t, i, 1)
|
|
assert n == sum(t, n - 1)
|
|
print(time.time() - start)
|
|
|
|
|
|
test()
|