Kotlin Leetcode - 771. Jewels and Stones

題目連接： https://leetcode.com/problems/jewels-and-stones/

class Solution {
    fun numJewelsInStones(jewels: String, stones: String): Int {
    }
}

解題思路

這題相對單純

就是用字串處理和比對

來找出石頭內是否有對應的寶石

Kotlin 參考解答

class Solution {
    fun numJewelsInStones(jewels: String, stones: String): Int {
        var ans = 0
        for (stone in stones) {
            if (jewels.contains(stone)) {
                ans++
            }
        }
        return ans
    }
}

這個邏輯可以更加簡化為一行

class Solution {
    fun numJewelsInStones(jewels: String, stones: String) = stones.count { it in jewels }
}

---

回到 leetcode 列表