> For the complete documentation index, see [llms.txt](https://koshizuow.gitbook.io/compilerbook/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://koshizuow.gitbook.io/compilerbook/function_local_variable.md).

# 函式與區域變數

本章會實作函式與區域變數。同時，也會實作簡單的控制架構。結束本章之後，應該要可以編譯如下的程式：

```c
// 從m開始累加到n
sum(m, n) {
  acc = 0;
  for (i = m; i <= n; i = i + 1)
    acc = acc + i;
  return acc;
}

main() {
  return sum(1, 10); // 回傳55
}
```

上述程式碼離C語法雖然還是有點遠，但應該可以說很像C了吧？


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