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# 巧用取模实现轮询效果

{% embed url="<https://v.douyin.com/r8RNXRu/>" %}

{% embed url="<https://www.bilibili.com/video/BV1V94y127fF/>" %}

前两天啊

copilot给我提示出来这样一句代码

我觉得挺有意思

就是这个

什么意思呢

原本啊我是想这样写

加加然后呢判断一下

如果他大于等于length让他等于

意思就是让这个

index 啊

在这个历史的里面做一个顺序的循环

比如012到这之后呢再

但是他这个写法呢也可以

什么意思

就是

先加

这个没问题

然后加1之后呢

拿这个结果再去取模这个长度

也就是说当他加到

这个长度的时候

一取模就回到0了

当然了严格来说

这样写的效率一定是不如下边这样的

因为这块每次都要做一个取模计算

但下边这种写法呢

他大部分情况只是做了一个比较

不过啊我还是做了下测试

这么写的话

1,000万次的循环呢

他会多花30毫秒左右

所以呢从这个时间上来看

我觉得啊

绝大部分项目

可以不用考虑他的效率问题

所以不知道如果让大家选择的话

大家更倾向于使用哪种方法


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