leetcodeブラシ記録

まだ剣をつけていないで、あっという間に江湖に行って、自分が書いた問題を記録します.array (1)twoSum Given an array of integers, return indices of the two numbers such that they add up to a specific target.You may assume that each input would have exactly one solution, and you may not use the same element twice. Example: Given nums = [2, 7, 11, 15], target = 9, Because nums[0] + nums[1] = 2 + 7 = 9, return [0, 1].
コード#コード#
配列を巡回し、巡回したvectorをmapに保存し、キー値をorderにし、findに行き、orderを返します.

using namespace std;
#include 
#include 
#include 
class Solution {
public:
    vector<int> twoSum(vector<int>& nums, int target) {
        map <int,int> hashmap;
        vector <int> result;
        for (int i = 0; i < nums.size(); i++) {
            int toFind = target - nums[i];
            if (hashmap.find(toFind) != hashmap.end()) {
                result.push_back(hashmap[toFind]);
                result.push_back(i+1);
                return result;
            }
            hashmap[nums[i]] = i;
        }
    }
};
//      ，  null, vector size 0，  。      o[n]