题目：原题链接（中等）
标签：树状数组、线段树
解法 | 时间复杂度 | 空间复杂度 | 执行用时 |
Ans 1 (Python) | O ( N l o g N ) | O ( 50000 ) | 100ms (71.83%) |
Ans 2 (Python) | |||
Ans 3 (Python) |
解法一：
class BIT:
def __init__(self, n: int):
self.n = n
self._tree = [0] * (n + 1)
@staticmethod
def _lowbit(x):
return x & (-x)
def update(self, i: int, x: int):
self.add(i, x - (self.query(i) - self.query(i - 1)))
def add(self, i: int, x: int):
while i <= self.n:
self._tree[i] += x
i += BIT._lowbit(i)
def query(self, i: int) -> int:
ans = 0
while i > 0:
ans += self._tree[i]
i -= BIT._lowbit(i)
return ans
def range_query(self, l: int, r: int) -> int:
return self.query(r) - self.query(l - 1)
class StreamRank:
def __init__(self):
self.B = BIT(50001)
def track(self, x: int) -> None:
self.B.add(x + 1, 1)
def getRankOfNumber(self, x: int) -> int:
return self.B.query(x + 1)
