Given an array
nums
of size n
, return the majority element.The majority element is the element that appears more than
⌊n / 2⌋
times. You may assume that the majority element always exists in the array.Example 1:
Input: nums = [3,2,3]
Output: 3
Example 2:
Input: nums = [2,2,1,1,1,2,2]
Output: 2
Constraints:
n == nums.length
1 <= n <= 5 * 10<sup>4</sup>
-2<sup>31</sup> <= nums[i] <= 2<sup>31</sup> - 1
*Follow-up: Could you solve the problem in linear time and in
O(1)
space?题目大意:
求数组中的众数
解题思路:
编程之美的水王法
解题步骤:
N/A
注意事项:
Python代码:
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12def majorityElement(self, nums: List[int]) -> int:
candidate, count = 0, 0
for i in range(len(nums)):
if count == 0:
candidate = nums[i]
count += 1
continue
if nums[i] == candidate:
count += 1
else:
count -= 1
return candidate
算法分析:
时间复杂度为O(n)
,空间复杂度O(1)