Non-overlapping Intervals

class Solution {
public:
    int eraseOverlapIntervals(vector<vector<int>>& intervals) {
        sort(intervals.begin(), intervals.end(), [](auto& a, auto& b){ return a[1] < b[1]; });
        int kept = 0, end = INT_MIN;
        for (auto& it : intervals) {
            if (it[0] >= end) { ++kept; end = it[1]; }
        }
        return intervals.size() - kept;
    }
};

import (
    "math"
    "sort"
)

func eraseOverlapIntervals(intervals [][]int) int {
    sort.Slice(intervals, func(i, j int) bool {
        return intervals[i][1] < intervals[j][1]
    })
    kept := 0
    end := math.MinInt32
    for _, it := range intervals {
        if it[0] >= end {
            kept++
            end = it[1]
        }
    }
    return len(intervals) - kept
}

from typing import List

class Solution:
    def eraseOverlapIntervals(self, intervals: List[List[int]]) -> int:
        intervals.sort(key=lambda x: x[1])
        kept = 0
        end = float('-inf')
        for it in intervals:
            if it[0] >= end:
                kept += 1
                end = it[1]
        return len(intervals) - kept

function eraseOverlapIntervals(intervals) {
    intervals.sort((a, b) => a[1] - b[1]);
    let kept = 0;
    let end = -Infinity;
    for (const it of intervals) {
        if (it[0] >= end) {
            kept++;
            end = it[1];
        }
    }
    return intervals.length - kept;
}

class Solution {
    public int eraseOverlapIntervals(int[][] intervals) {
        Arrays.sort(intervals, (a, b) -> a[1] - b[1]);
        int kept = 0;
        int end = Integer.MIN_VALUE;
        for (int[] it : intervals) {
            if (it[0] >= end) {
                kept++;
                end = it[1];
            }
        }
        return intervals.length - kept;
    }
}

function eraseOverlapIntervals(intervals: number[][]): number {
    intervals.sort((a, b) => a[1] - b[1]);
    let kept = 0;
    let end = -Infinity;
    for (const it of intervals) {
        if (it[0] >= end) {
            kept++;
            end = it[1];
        }
    }
    return intervals.length - kept;
}