javascript - Find the optimal solution for the intersection between time periods

Question

Determine whether there is an intersection between a period of time and a bunch of periods of time. If the start and end times are the same, it is judged that there is an intersection
such as

判断 
12:30:00--14:20:00
与下列时间段是否有交集
10:00:00-12:00:00,  12:10:00-12:50:00 , 14:30:00-15:00:00

Convert to timestamp and then compare them one by one in a loop

function is_cross($st1, $et1, $st2, $et2)
    {
        $status = $st2 - $st1;
        if ($status > 0) {
            $status2 = $st2 - $et1;
            if ($status2 >= 0) {
                return false;
            } else {
                return true;
            }
        } else {
            $status2 = $et2 - $st1;
            if ($status2 > 0) {
                return true;
            } else {
                return false;
            }
        }
    }

This can solve the problem, but we are looking for a better method with the smallest time complexity

Answer 1

public function inter(){

    $tar=[6,4];
    if($tar[0]>$tar[1]){
        $temp=$tar[0];
        $tar[0]=$tar[1];
        $tar[1]=$temp;
    }
    $all=[
        [5,6],
        [7,9],
        [1,4],
        [3,1],
        [1,3],
        [8,7]
    ];
    //排序
    foreach ($all as &$v){
        if($v[0]>$v[1]){
            $temp=$v[0];
            $v[0]=$v[1];
            $v[1]=$temp;
        }
    }
    foreach ($all as $k=>$v){
        $left=$tar[0]>$v[1];
        $right=$v[0]>$tar[1];
        if(!($left||$right)){
            var_dump($v);
        }
    }

}

Answer 2

Convert the time into a timestamp, and then ------- compare.

Answer 3

If this a bunch of time needs to be used multiple times: you can use a line segment tree. "One-to-one comparison" will not be slower when used once.

Answer 4

# -*- coding: utf-8 -*-

def is_mixed(t1, t2):
    '''
    假定时间段格式是："10:00:00-12:00:00"
    判断 t1，t2是否有交集
    '''
    s1, e1 = t1.split("-")
    s2, e2 = t2.split("-")

    if s1 > e2 and s2 > e1:
        return True
    if s2 > e1 and s1 > e2:
        return True

    return False

t1 = "12:30:00-04:20:00"
t2 = "03:00:00-22:23:00"

if is_mixed(t1, t2):
    print "有交集!"
else:
    print "木有交集!"

Python version, js should be the same

Answer 5

转换成时间戳能方便比较点

Answer 6

In this way, you can select the time period that overlaps with period from periods.

period  = "12:30:00-14:20:00"
periods  = ["10:00:00-12:00:00", "12:10:00-12:50:00","14:30:00-15:00:00"]

print([x+'-'+y for [b,e] in [period.split("-")] for [x,y] in [p.split("-") for p in periods] if x<=e and y>=b])

Answer 7

Convert the time into an integer 123000, and judge in reverse
a -- b
c -- d
Under what circumstances do these two time periods not overlap?

1. b < c

2. a > d