435. Non-overlapping Intervals - LeetCode Solution

class Solution:
    def eraseOverlapIntervals(self, intervals: List[List[int]]) -> int:
        if not intervals:
            return 0
        intervals.sort(key = lambda x: x[0])
        cur = intervals[0][1]
        ans = 0
        for start, end in intervals[1:]:
            if start < cur:
                cur = min(cur, end)
                ans += 1
            else:
                cur = end
        return ans