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[8/3] 729. My Calendar I

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작성일 2022.08.02 21:36

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You are implementing a program to use as your calendar. We can add a new event if adding the event will not cause a double booking.

A double booking happens when two events have some non-empty intersection (i.e., some moment is common to both events.).

The event can be represented as a pair of integers start and end that represents a booking on the half-open interval [start, end), the range of real numbers x such that start <= x < end.

Implement the MyCalendar class:

MyCalendar() Initializes the calendar object.
boolean book(int start, int end) Returns true if the event can be added to the calendar successfully without causing a double booking. Otherwise, return false and do not add the event to the calendar.

Example 1:

Input
["MyCalendar", "book", "book", "book"]
[[], [10, 20], [15, 25], [20, 30]]
Output
[null, true, false, true]

Explanation
MyCalendar myCalendar = new MyCalendar();
myCalendar.book(10, 20); // return True
myCalendar.book(15, 25); // return False, It can not be booked because time 15 is already booked by another event.
myCalendar.book(20, 30); // return True, The event can be booked, as the first event takes every time less than 20, but not including 20.

Constraints:

0 <= start < end <= 109
At most 1000 calls will be made to book.

#Google, #Uber, #Twitch, #Binary Search, #Design, #Segment Tree, #Ordered Set

링크

https://leetcode.com/problems/my-calendar-i/ 1320 회 연결

익명
작성일 2022.08.02 21:50

Runtime: 415 ms, faster than 57.90% of Python3 online submissions for My Calendar I.
Memory Usage: 14.7 MB, less than 92.29% of Python3 online submissions for My Calendar I.

class MyCalendar:

    def __init__(self):
        self.items = []

    def book(self, start: int, end: int) -> bool:
        if not self.items: 
            self.items.append(start); self.items.append(end);
            return True
        
        left, right = self.binary_right(start), self.binary_left(end)
        if left!=right or left%2: return False
        
        self.items.insert(left, start)
        self.items.insert(left+1,end)
        return True
        
        
        
    def binary_left(self, num):
        l, r = 0, len(self.items)
        
        while l < r:
            mid = (l+r)//2
            
            if self.items[mid] < num:
                l = mid + 1
            else:
                r = mid
        return l
    
    def binary_right(self,num):
        l, r = 0, len(self.items)
        while l < r:
            mid = (l+r)//2
            
            if self.items[mid] <= num:
                l = mid + 1
            else:
                r = mid
        return l
        
        

# Your MyCalendar object will be instantiated and called as such:
# obj = MyCalendar()
# param_1 = obj.book(start,end)

Runtime: 415 ms, faster than 57.90% of Python3 online submissions for My Calendar I.
Memory Usage: 14.7 MB, less than 92.29% of Python3 online submissions for My Calendar I.
[code=Python 3]class MyCalendar:

def __init__(self):
        self.items = []

def book(self, start: int, end: int) -> bool:
        if not self.items: 
            self.items.append(start); self.items.append(end);
            return True
        
        left, right = self.binary_right(start), self.binary_left(end)
        if left!=right or left%2: return False
        
        self.items.insert(left, start)
        self.items.insert(left+1,end)
        return True
        
        
        
    def binary_left(self, num):
        l, r = 0, len(self.items)
        
        while l < r:
            mid = (l+r)//2
            
            if self.items[mid] < num:
                l = mid + 1
            else:
                r = mid
        return l
    
    def binary_right(self,num):
        l, r = 0, len(self.items)
        while l < r:
            mid = (l+r)//2
            
            if self.items[mid] <= num:
                l = mid + 1
            else:
                r = mid
        return l

# Your MyCalendar object will be instantiated and called as such:
# obj = MyCalendar()
# param_1 = obj.book(start,end)[/code]