30 Day Challenge Day 10 | Leetcode 1. Two Sum

题解

方法：哈希表

class Solution {
public:
    vector<int> twoSum(vector<int>& nums, int target) {
        unordered_map<int, int> hash;
        for(int i = 0; i < nums.size(); i++) {
            if(hash.count(target-nums[i])) {
                return {hash[target-nums[i]], i};
            }
            hash[nums[i]] = i;
        }
        return {};
    }
};