[LeetCode] 169

Given an array of size n, find the majority element. The majority element is the element that appears more than ⌊ n/2 ⌋ times.

You may assume that the array is non-empty and the majority element always exist in the array.

class Solution {
public:
  int majorityElement(vector<int>& nums) {
#if 0
    std::sort(nums.begin(), nums.end());
    return nums[nums.size() / 2 ];
#else
    unordered_map<int, int> maps;
    int times = (nums.size() + 1) / 2;
    for (auto c : nums) {
      maps[c]++;
      if (maps[c] >= times) {
        return c;
      }
    }
#endif
  }
};

原文地址:https://www.cnblogs.com/shoemaker/p/4765957.html