5-Big O Notation

一、基本内容 1,Big 𝑶 is always concerned with worst case time requirement

2,Big O计算: 看最高次项,忽略系数 image1

平行的O相加,内嵌的O相乘

![image2](../../assets/9dc90470253d4a6eb68c033c45a9dbc7.png)

![image3](../../assets/fe381713595545028a3bf1762501945f.png)

3,search

linear Search Binary Search

![image4](../../assets/83286aec962041a5aac28eb8d96d6f8a.png)

![image5](../../assets/967ec3d2d17b4996a6b89940a79f7d91.png)

4,基本操作的big O image6

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二、Formalities

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![image9](../../assets/544d70a4e78b46af9d9f3552649f7b20.png)

![image10](../../assets/951bda5b5bb547e1818c28c2463863c1.png)

![image11](../../assets/74992ac7aeff49cfb3e39397b8378888.png)

![image12](../../assets/c2f0367e821d4c438a23ccc19b21ee09.png)

![image13](../../assets/db5c3024a2b94889b90ba8c5e0709c4e.png)

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三、Usage 1,一直用最简形式来描述O-notation image15

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五、Getting Big O of a program 1, image18

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重点 image21

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