在递归模式下实现三元搜索！三元搜索遵循相同的二叉搜索思想，但将向量分为3个部分，两个索引：一个为左侧，一个为右侧，第三个搜索为中间！-implement a ternary search in recursivity mode. The ternary search follows the same idea of binary search, but splitting the vector into 3 parts, two index: One for left and one to the right and a third search in the middle!