1-TwoSum.md

class Solution 
{
public:
    vector<int> twoSum(vector<int>& nums, int target)
    {
        //哈希
        if (nums.size() == 0) return {};
        unordered_map<int, int> mp;
        for (int i = 0; i < nums.size(); i++)
        {
            if (mp.find(target - nums[i]) != mp.end())
            {
                return {i, mp[target - nums[i]]};
            }
            mp[nums[i]] = i;
        }
        return {};
    }
};