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Sort intervals by start time, check if any meeting starts before previous ends.
Example:
Input:
intervals=[[0,30],[5,10],[15,20]]Output:
false (overlap between [0,30] and [5,10])Common Mistakes:
- Not sorting intervals first
- Wrong overlap condition (should be start < previous end)
- Overcomplicating with sweep line when simple iteration suffices
- Checking all pairs O(n²) instead of sorted O(n) scan
Notes:
Simple interval problem. Time O(n log n) for sorting, Space O(1) or O(n) depending on sort. Premium problem on LeetCode.
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Sort intervals by start time, check if any meeting starts before previous ends.
Example:
Input:
intervals=[[0,30],[5,10],[15,20]]Output:
false (overlap between [0,30] and [5,10])Common Mistakes:
- Not sorting intervals first
- Wrong overlap condition (should be start < previous end)
- Overcomplicating with sweep line when simple iteration suffices
- Checking all pairs O(n²) instead of sorted O(n) scan
Notes:
Simple interval problem. Time O(n log n) for sorting, Space O(1) or O(n) depending on sort. Premium problem on LeetCode.
70/75
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