# 修改默认程序

在[探索默认项目](https://github.com/chengshuzhi/DfinityTutorials/tree/67efaf95e3f292cfe2fc958ffec63d10ccf7a6f9/si-.-jiao-cheng/1.-tan-suo-mo-ren-xiang-mu)章节，已经介绍了创建新项目会创建一个默认的src目录，并包含一个main.mo程序模板文件。

源码修改步骤

1.编辑器中打开src/location\_hello/main.mo 源码文件。

2.修改默认源码，用有city参数的location函数替换greet函数。

例如

```
actor {
 public func location(city : Text) : async Text {
 return "Hello, " # city # "!";
 };
};
```

3\. 保存并关闭文件。


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