题解 | 宝石计数

import java.util.*;

public class Solution {
    public int numJewelsInStones (String jewels, String stones) {
        HashMap<Character,Integer> map = new HashMap<>();
        int ans = 0;
        for(int i=0;i<jewels.length();i++){
            map.put(jewels.charAt(i),1);
        }
        for(int i=0;i<stones.length();i++){
            int cur = map.getOrDefault(stones.charAt(i),0);
            ans += cur;
        }
        return ans;
    }
}