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🟩 Meeting Rooms (#252) 🔒

🔗 Problem Link​

📋 Problem Statement​

Given an array of meeting time intervals where intervals[i] = [starti, endi], determine if a person could attend all meetings.

Note: This is a premium LeetCode problem, but available for free on NeetCode.

💡 Examples​

Example 1​

Input: intervals = [[0,30],[5,10],[15,20]]
Output: false

Example 2​

Input: intervals = [[7,10],[2,4]]
Output: true

🔑 Key Insights & Approach​

Core Observation: Sort by start time, check if any meetings overlap.

Why Sort?

  • O(n log n) time
  • Linear scan after sorting
  • Overlaps if start[i] < end[i-1]

Pattern: "Interval Overlap Detection" pattern.

🐍 Solution: Python​

Approach: Sort and Check​

Time Complexity: O(n log n) | Space Complexity: O(1)

from typing import List

class Solution:
    def canAttendMeetings(self, intervals: List[List[int]]) -> bool:
        if not intervals:
            return True

        intervals.sort(key=lambda x: x[0])

        for i in range(1, len(intervals)):
            if intervals[i][0] < intervals[i-1][1]:
                return False

        return True

🔵 Solution: Golang​

Approach: Sort and Check​

Time Complexity: O(n log n) | Space Complexity: O(1)

import "sort"

func canAttendMeetings(intervals [][]int) bool {
    if len(intervals) == 0 {
        return true
    }

    sort.Slice(intervals, func(i, j int) bool {
        return intervals[i][0] < intervals[j][0]
    })

    for i := 1; i < len(intervals); i++ {
        if intervals[i][0] < intervals[i-1][1] {
            return false
        }
    }

    return true
}

📚 References​