You’re given strings J representing the types of stones that are jewels, and S representing the stones you have.  Each character in S is a type of stone you have.  You want to know how many of the stones you have are also jewels.

The letters in J are guaranteed distinct, and all characters in J and S are letters. Letters are case sensitive, so “a” is considered a different type of stone from “A”.

Example 1:

Input: J = “aA”, S = “aAAbbbb” Output: 3

Example 2:

Input: J = “z”, S = “ZZ” Output: 0

Note:

  • S and J will consist of letters and have length at most 50.
  • The characters in J are distinct.

Solution

For each character of S, do lookup in the Jewel String J. We can use HashSet to store Jewel Characters to make fast lookup.

Code

Output

3

We encourage you to write a comment if you have a better solution or having any doubt on the above topic.

Leave a Reply

Your email address will not be published. Required fields are marked *