SOURCE

let data = 
[
                {
                    "facilityScheduleId": 6559855,
                    "scheduleDate": "2025-07-03",
                    "startTime": "8:00",
                    "endTime": "9:00",
                    "fee": 150,
                    "point": 0,
                    "available": false
                },{
                    "facilityScheduleId": 6559855,
                    "scheduleDate": "2025-07-03",
                    "startTime": "9:00",
                    "endTime": "10:00",
                    "fee": 150,
                    "point": 0,
                    "available": false
                },{
                    "facilityScheduleId": 6559855,
                    "scheduleDate": "2025-07-03",
                    "startTime": "10:00",
                    "endTime": "11:00",
                    "fee": 150,
                    "point": 0,
                    "available": false
                },{
                    "facilityScheduleId": 6559855,
                    "scheduleDate": "2025-07-03",
                    "startTime": "11:00",
                    "endTime": "12:00",
                    "fee": 150,
                    "point": 0,
                    "available": false
                },
                {
                    "facilityScheduleId": 6559856,
                    "scheduleDate": "2025-07-03",
                    "startTime": "12:00",
                    "endTime": "13:00",
                    "fee": 150,
                    "point": 0,
                    "available": false
                },
                {
                    "facilityScheduleId": 6559857,
                    "scheduleDate": "2025-07-03",
                    "startTime": "13:00",
                    "endTime": "14:00",
                    "fee": 150,
                    "point": 0,
                    "available": false
                },
                {
                    "facilityScheduleId": 6559858,
                    "scheduleDate": "2025-07-03",
                    "startTime": "14:00",
                    "endTime": "15:00",
                    "fee": 150,
                    "point": 0,
                    "available": false
                },
                {
                    "facilityScheduleId": 6559859,
                    "scheduleDate": "2025-07-03",
                    "startTime": "15:00",
                    "endTime": "16:00",
                    "fee": 150,
                    "point": 0,
                    "available": false
                },
                {
                    "facilityScheduleId": 6559860,
                    "scheduleDate": "2025-07-03",
                    "startTime": "16:00",
                    "endTime": "17:00",
                    "fee": 150,
                    "point": 0,
                    "available": false
                },
                {
                    "facilityScheduleId": 6559861,
                    "scheduleDate": "2025-07-03",
                    "startTime": "17:00",
                    "endTime": "18:00",
                    "fee": 150,
                    "point": 0,
                    "available": false
                },
                {
                    "facilityScheduleId": 6559862,
                    "scheduleDate": "2025-07-03",
                    "startTime": "18:00",
                    "endTime": "19:00",
                    "fee": 330,
                    "point": 0,
                    "available": false
                },
                {
                    "facilityScheduleId": 6559863,
                    "scheduleDate": "2025-07-03",
                    "startTime": "19:00",
                    "endTime": "20:00",
                    "fee": 330,
                    "point": 0,
                    "available": false
                },
                {
                    "facilityScheduleId": 6559864,
                    "scheduleDate": "2025-07-03",
                    "startTime": "20:00",
                    "endTime": "21:00",
                    "fee": 330,
                    "point": 0,
                    "available": false
                },
                {
                    "facilityScheduleId": 6559865,
                    "scheduleDate": "2025-07-03",
                    "startTime": "21:00",
                    "endTime": "22:00",
                    "fee": 330,
                    "point": 0,
                    "available": false
                }
            ]
console.log(data.length)