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# 387.First Unique Character in a String

**387.First Unique Character in a String**

难度:Easy

> 给定一个字符串，找到它的第一个不重复的字符，并返回它的索引。如果不存在，则返回 -1。

案例:

```
s = "leetcode"
返回 0.

s = "loveleetcode",
返回 2.
```

注意事项：您可以假定该字符串只包含小写字母。 简单题，代码如下:

```
class Solution {
public:
    int firstUniqChar(string s) {
        unordered_map<char,int> tmp;
        for(auto c: s)
            tmp[c]++;
        for(int i=0;i<s.length();i++)
        {
            if(tmp[s[i]]==1) return i;
        }
        return -1;
        
    }
};
```