{ "data": { "question": { "questionId": "100240", "questionFrontendId": "面试题 08.03", "categoryTitle": "LCCI", "boundTopicId": 61486, "title": "Magic Index LCCI", "titleSlug": "magic-index-lcci", "content": "

A magic index in an array A[0...n-1] is defined to be an index such that A[i] = i. Given a sorted array of integers, write a method to find a magic index, if one exists, in array A. If not, return -1. If there are more than one magic index, return the smallest one.

\r\n\r\n

Example1:

\r\n\r\n
\r\n Input: nums = [0, 2, 3, 4, 5]\r\n Output: 0\r\n
\r\n\r\n

Example2:

\r\n\r\n
\r\n Input: nums = [1, 1, 1]\r\n Output: 1\r\n
\r\n\r\n

Note:

\r\n\r\n
    \r\n\t
  1. 1 <= nums.length <= 1000000
  2. \r\n\t
  3. This problem is the follow-up of the original problem in the book, i.e. the values are not distinct.
  4. \r\n
\r\n", "translatedTitle": "魔术索引", "translatedContent": "

魔术索引。 在数组A[0...n-1]中,有所谓的魔术索引,满足条件A[i] = i。给定一个有序整数数组,编写一种方法找出魔术索引,若有的话,在数组A中找出一个魔术索引,如果没有,则返回-1。若有多个魔术索引,返回索引值最小的一个。

\n\n

示例1:

\n\n
 输入:nums = [0, 2, 3, 4, 5]\n 输出:0\n 说明: 0下标的元素为0\n
\n\n

示例2:

\n\n
 输入:nums = [1, 1, 1]\n 输出:1\n
\n\n

说明:

\n\n
    \n\t
  1. nums长度在[1, 1000000]之间
  2. \n\t
  3. 此题为原书中的 Follow-up,即数组中可能包含重复元素的版本
  4. \n
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