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$ curl repovive.com/roadmaps/pattern-22/intervals/non-overlapping-intervals-implementation

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$ curl repovive.com/roadmaps/pattern-22/intervals/non-overlapping-intervals-implementation

Repovive

LeetCode 435 Non-overlapping Intervals - Implementation - Intervals | Pattern 22: LeetCode Interview Patterns | Repovive

Repovive.

Pattern 22: LeetCode Interview Patterns24 sections · 736 units32h total

Open in Course

LeetCode 435 Non-overlapping Intervals - Implementation

The approach

Sort by end time. Greedily keep non-overlapping intervals.

def eraseOverlapIntervals(intervals): intervals.sort(key=lambda x: x[1]) removed = 0 lastEnd = float('-inf')

for start, end in intervals:
    if start >= lastEnd:
        lastEnd = end
    else:
        removed += 1

return removed

$O(n \log n)$ time, $O(1)$ extra space.