intervals non-overlapping

Given an array of intervals such that interval[i] = [starti, endi], return the minimum number of intervals needed to remove for making the remaining intervals non-overlapping.

Input Format

First Parameter - matrix intervals of size m x n

Output Format

Return the number.

Example 1:

Input:
    4 2
    1 2
    2 3
    3 4 
    1 3
Output: 1
Explanation: 4 2 represents the size of the interval. 1 3 can be removed and the rest of the intervals are non-overlapping.

Example 2:

Input:
    3 2
    1 2
    1 2
    1 2
Output: 2
Explanation: 3 2 represents the size of the intervals. You need to remove two [1,2] to make the rest of the intervals 
non-overlapping.

Constraints:

• 1 <= interval.length <= 105
• interval[i].length == 2
• -5 * 104 <= start[i] < end[i] <= 5 * 104
• Expected Time Complexity: O(n logn)
• Expected Auxiliary Space: O(1)