jewels-and-stones-771.go

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

Letters are case sensitive, so "a" is considered a different type of stone from "A".

 

Example 1:

Input: jewels = "aA", stones = "aAAbbbb"
Output: 3
Example 2:

Input: jewels = "z", stones = "ZZ"
Output: 0
 

Constraints:

1 <= jewels.length, stones.length <= 50
jewels and stones consist of only English letters.
All the characters of jewels are unique.
*/

func numJewelsInStones(jewels string, stones string) int {
    matches := 0

    // Initially, I wanted to use a hash table (map).
    // Seems it could improve performance but it also seemed like overkill this morning, lol.
    for _, stone := range stones {
        for _, jewel := range jewels {
            if stone == jewel {
                matches++
                break
            }
        }
    }

    return matches
}