Daily LeetCode – day0061 面试题 17.09. Get Kth Magic Number LCCI

// 面试题 17.09. Get Kth Magic Number LCCI
class Solution {
    public int getKthMagicNumber(int k) {
        int[] magicNumbers = new int[k + 1];
        magicNumbers[1] = 1;
        int pointer3 = 1;
        int pointer5 = 1;
        int pointer7 = 1;
        for (int i = 2; i <= k; ++i) {
            int min = Math.min(Math.min(magicNumbers[pointer3] * 3, magicNumbers[pointer5] * 5), magicNumbers[pointer7] * 7);
            if (min == magicNumbers[pointer3] * 3) ++pointer3;
            if (min == magicNumbers[pointer5] * 5) ++pointer5;
            if (min == magicNumbers[pointer7] * 7) ++pointer7;
            magicNumbers[i] = min;
        }
        return magicNumbers[k];
    }
}

学习笔记：
这是一道简单的题目，之前有教过学生。
就是比较三个数里面最小的，添加到数组里面。
找到第k个数字。