leetCode题解之Jewels and Stones

1、题目描述

2、分析

　　使用HashTable 是解决这种的好方法。

3、代码

 1 int numJewelsInStones(string J, string S) {
 2         map<char,int> m;
 3         for(char c : S)
 4             m[c]++;
 5
 6         int ans = 0;
 7         for( char c: J)
 8             ans += m[c];
 9         return ans;
10
11     }

原文地址：https://www.cnblogs.com/wangxiaoyong/p/8929669.html

时间： 2024-08-30 18:00:40

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