66 lines
1017 B
Org Mode
66 lines
1017 B
Org Mode
#+title: 136 Single Number
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Given a non-empty array of integers nums, every element appears twice except for one. Find that single one.
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You must implement a solution with a linear runtime complexity and use only constant extra space.
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Example 1:
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Input: nums = [2,2,1]
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Output: 1
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Example 2:
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Input: nums = [4,1,2,1,2]
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Output: 4
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Example 3:
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Input: nums = [1]
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Output: 1
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Constraints:
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1 <= nums.length <= 3 * 104
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-3 * 104 <= nums[i] <= 3 * 104
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Each element in the array appears twice except for one element which appears only once.
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* Solution
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#+name: solution
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#+begin_src C
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int xor(int a, int b) {
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return a ^ b;
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}
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int singleNumber(int* nums, int numsSize) {
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int number = 0;
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for (int i=0; i < numsSize; i++) {
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number = xor(number, nums[i]);
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}
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return number;
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}
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#+end_src
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#+RESULTS: solution
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#+begin_src C :noweb yes
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#include <stdio.h>
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<<solution>>
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int numbers[3] = {1, 1, 2};
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int single = singleNumber(numbers, 3);
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printf("%d\n", single);
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#+end_src
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#+RESULTS:
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: -2
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