[LeetCode]Non-overlapping Intervals@Python

Non-overlapping Intervals

Given a collection of intervals, find the minimum number of intervals you need to remove to make the rest of the intervals non-overlapping.
Note:
You may assume the interval’s end point is always bigger than its start point.
Intervals like [1,2] and [2,3] have borders “touching” but they don’t overlap each other.

Example

Input: [ [1,2], [2,3], [3,4], [1,3] ]
Output: 1
Explanation: [1,3] can be removed and the rest of intervals are non-overlapping.

Solution

class Solution(object):
    def eraseOverlapIntervals(self, intervals):
        """
        :type intervals: List[List[int]]
        :rtype: int
        """
        end = float('-inf')
        erased = 0
        for i in sorted(intervals, key = lambda i:i[1]):
            if i[0] >= end:
                end = i[1]
            else:
                erased += 1
                end = min(end, i[1])
        return erased