题解 | #数组中只出现一次的两个数字#

哈希表

#include <unordered_map>
#include <vector>
class Solution {
public:
    vector<int> FindNumsAppearOnce(vector<int>& nums) {
        unordered_map<int, int> hash;
        for (int i=0; i<nums.size(); i++) {
            if (hash.find(nums[i])==hash.end()) {
                hash[nums[i]]=1;
            }else {
                hash.erase(nums[i]);
            }
        }
        vector<int> res;
        auto a = hash.begin(), b=++hash.begin();
        if (a->first>b->first) {
            res.push_back(b->first);
            res.push_back(a->first);
        }else {
            res.push_back(a->first);
            res.push_back(b->first);
        }
        return res;
    }
};