> For the complete documentation index, see [llms.txt](https://dfine.gitbook.io/leetcode/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://dfine.gitbook.io/leetcode/709.to_lower_case.md).

# 709.To Lower Case

**709.To Lower Case**

难度:Easy

> 实现函数 ToLowerCase()，该函数接收一个字符串参数 str，并将该字符串中的大写字母转换成小写字母，之后返回新的字符串。

```
示例 1：
输入: "Hello"
输出: "hello"
示例 2：
输入: "here"
输出: "here"
示例 3：
输入: "LOVELY"
输出: "lovely"
```

简单题，代码如下：

```
class Solution {
public:
    string toLowerCase(string str) {
        string res;
        for(auto i:str)
            res+= (i<91 && i>64)?i+32:i;
        return res;
    }
};
```


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