# 771.Jewels and Stones

**771.Jewels and Stones**

难度:Easy

> 给定字符串J 代表石头中宝石的类型，和字符串 S代表你拥有的石头。 S 中每个字符代表了一种你拥有的石头的类型，你想知道你拥有的石头中有多少是宝石。

J 中的字母不重复，J 和 S中的所有字符都是字母。字母区分大小写，因此"a"和"A"是不同类型的石头。

```
示例 1:
输入: J = "aA", S = "aAAbbbb"
输出: 3
示例 2:
输入: J = "z", S = "ZZ"
输出: 0
注意:
S 和 J 最多含有50个字母。
 J 中的字符不重复。
```

简单题，代码如下：

```
class Solution {
public:
    int numJewelsInStones(string J, string S) {
        unordered_set<char> temp(J.begin(),J.end());
       // cout<< temp.count(J[0])<<endl;
        int total=0;
        for(auto i: S)
            total= temp.count(i) ? total+1 : total;
        return total;
    }
};
```


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