덧셈하여 타겟을 만들 수 있는 배열의 두 인덱스를 리턴하라
Input: nums = [2,7,11,15], target = 9
Output: [0,1]
Explanation: Because nums[0] + nums[1] == 9, we return [0, 1].
Input: nums = [3,2,4], target = 6
Output: [1,2]
Input: nums = [3,3], target = 6
Output: [0,1]
class Solution {
public:
vector<int> twoSum(vector<int>& nums, int target) {
vector<int> ans;
unordered_map <int, int> m;
for (int i = 0; i < nums.size(); i++) {
if (m.find(target - nums[i]) != m.end()) {
ans.push_back(m[target - nums[i]]);
ans.push_back(i);
return ans;
}
m[nums[i]] = i;
}
return {};
}
};
Runtime 3 ms / Memory 10.9 MB
https://leetcode.com/problems/two-sum/submissions/880012572/