2026-06-01 18:12:40 +08:00
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#+ANKI_DECK: study_deck_02
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2026-06-01 17:12:10 +08:00
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* TODO 0268. Missing Number :easy:
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2026-06-01 02:33:30 +08:00
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:PROPERTIES:
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2026-06-01 17:22:07 +08:00
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:NEETCODE: [[file:../../roadmap.org::*0268. Missing Number][0268. Missing Number]]
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2026-06-01 02:33:30 +08:00
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:END:
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2026-06-01 17:22:07 +08:00
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Given an array ~nums~ containing ~n~ distinct numbers in the range ~[0, n]~, return /the only number in the range that is missing from the array./
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*Example 1:*
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*Input:* nums = [3,0,1]
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*Output:* 2
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*Explanation:*
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~n = 3~ since there are 3 numbers, so all numbers are in the range ~[0,3]~. 2 is the missing number in the range since it does not appear in ~nums~.
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*Example 2:*
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*Input:* nums = [0,1]
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*Output:* 2
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*Explanation:*
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~n = 2~ since there are 2 numbers, so all numbers are in the range ~[0,2]~. 2 is the missing number in the range since it does not appear in ~nums~.
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*Example 3:*
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*Input:* nums = [9,6,4,2,3,5,7,0,1]
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*Output:* 8
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*Explanation:*
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~n = 9~ since there are 9 numbers, so all numbers are in the range ~[0,9]~. 8 is the missing number in the range since it does not appear in ~nums~.
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*Constraints:*
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- ~n == nums.length~
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- ~1 <= n <= 10^{4}~
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- ~0 <= nums[i] <= n~
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- All the numbers of ~nums~ are *unique*.
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*Follow up:* Could you implement a solution using only ~O(1)~ extra space complexity and ~O(n)~ runtime complexity?
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2026-06-01 02:39:53 +08:00
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** TODO Approach
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Write your approach here.
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** TODO Python
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2026-06-05 22:32:49 +08:00
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#+begin_src python :lc-problem 268 :lc-lang python3
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2026-06-01 17:22:07 +08:00
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class Solution:
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def missingNumber(self, nums: List[int]) -> int:
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2026-06-01 02:39:53 +08:00
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#+end_src
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** TODO C++
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2026-06-05 22:32:49 +08:00
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#+begin_src cpp :lc-problem 268
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2026-06-01 17:22:07 +08:00
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class Solution {
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public:
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int missingNumber(vector<int>& nums) {
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}
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};
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2026-06-01 02:33:30 +08:00
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#+end_src
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