Majority Element II

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Given an integer array of size n, find all elements that appear more than ⌊ n/3 ⌋ times. The algorithm should run in linear time and in O(1) space.

解题思路:
(1)定义两个大小为2数组,一个为temp[2]存储元素,一个为times[2]存储次数
(2)若当前元素不同于temp数组中的元素,且times数组中有0,则将相应的元素用当前元素取代,并置相应的times为1
(3)若当前元素不同于temp数组中的元素,且times数组中没有0,则将times中的所有元素均减1
(4)若当前元素与temp数组中的某个元素相同,则将其对应的times增1;
(5)最后统计元素出现的次数是否满足条件的要求

int* majorityElement(int* nums, int numsSize, int* returnSize) {

if (nums == NULL || numsSize == 0)    return NULL;int* returnNums = (int*)malloc(sizeof(int)*2);int temp[2] = {NULL,NULL};int times[2] = {0,0};for (int i = 0; i < numsSize; i++){    if (times[0] == 0 && nums[i] != temp[1])    {        times[0] = 1;        temp[0] = nums[i];    }    else if (times[1] == 0 && nums[i] != temp[0])    {        times[1] = 1;        temp[1] = nums[i];    }    else if (nums[i] != temp[0] && nums[i] != temp[1])    {        times[0]--;        times[1]--;    }    else if (nums[i] == temp[0])    {        times[0]++;    }    else    {        times[1]++;    }}*returnSize = 0;for (int i = 0; i < 2; i++){    if (times[i] != 0)    {        int count = 0;        for (int j = 0; j < numsSize; j++)        {            if (temp[i] == nums[j])                count++;        }        if (count > numsSize/3)        {            returnNums[(*returnSize)++] = temp[i];        }    }}return returnNums;

}

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