Delete a checkpoint
let p = head; // 遍历链表的指针
，更多细节参见Line官方版本下载
return _apply.call(origAppend, this, arguments);
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Ultrahuman Ring Pro hasn’t just got a far bigger battery, it’s been re-engineered from the ground up. The company’s Bhuvan Srinivasan explained the older hardware had been pushed to its limit, especially in terms of the data it could process. Consequently, the Pro is equipped with a dual core processor with on-device machine learning to better crunch the numbers your body is throwing out. Its memory has also been increased, holding up to 250 days of data before it needs to sync with your smartphone. As well as improvements to durability, the new ring is also easier to cut apart in the hopefully rare event your finger, or its battery, begins to swell.