# 715. Range Module
A Range Module is a module that tracks ranges of numbers. Your task is to design and implement the following interfaces in an efficient manner.
addRange(int left, int right)
Adds the half-open interval [left, right), tracking every real number in that interval. Adding an interval that partially overlaps with currently tracked numbers should add any numbers in the interval [left, right) that are not already tracked.
queryRange(int left, int right)
Returns true if and only if every real number in the interval [left, right) is currently being tracked.
removeRange(int left, int right)
Stops tracking every real number currently being tracked in the interval [left, right).
Example:
addRange(10, 20): null
removeRange(14, 16): null
queryRange(10, 14): true (Every number in [10, 14) is being tracked)
queryRange(13, 15): false (Numbers like 14, 14.03, 14.17 in [13, 15) are not being tracked)
queryRange(16, 17): true (The number 16 in [16, 17) is still being tracked, despite the remove operation)
# Solution
Approach 1: keep a sorted list of disjoint intervals. Insert and Delete take O(N)
, Query takes O(logN)
.
# Code (Python)
Approach 1:
import bisect
class RangeModule:
def __init__(self):
self.ranges = []
def addRange(self, left: int, right: int) -> None:
if not self.ranges:
self.ranges = [[left, right]]
before, after = [], []
inserted = [left, right]
for interval in self.ranges:
if interval[1] < left:
before.append(interval)
elif interval[0] > right:
after.append(interval)
else:
inserted = [min(inserted[0], interval[0]), max(inserted[1], interval[1])]
self.ranges = before + [inserted] + after
def queryRange(self, left: int, right: int) -> bool:
index = bisect.bisect_left([interval[0] for interval in self.ranges], left)
for i in (index - 1, index):
if 0 <= i < len(self.ranges) and self.ranges[i][0] <= left and self.ranges[i][1] >= right:
return True
return False
def removeRange(self, left: int, right: int) -> None:
before, after, mid = [], [], []
for interval in self.ranges:
if interval[1] < left:
before.append(interval)
elif interval[0] > right:
after.append(interval)
else:
if interval[0] < left:
mid.append([interval[0], left])
if interval[1] > right:
mid.append([right, interval[1]])
self.ranges = before + mid + after
# Code (C++)
Approach 1:
Approach 2: