【LeetCode】两数之和

class Solution {
public:
    vector<int> twoSum(vector<int>& nums, int target) {
        vector<int> v(2,0);
        unordered_map<int,int> hashtable;
        for(int i=nums.size();i--;hashtable[nums[i]]=i){
            if(hashtable.find(target-nums[i])==hashtable.end()) continue;
            v[0]=i;
            v[1]=hashtable[target-nums[i]];
            return v;
        }
        return v;
    }
};