題目說明：

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.

Example:

Given nums = [2, 7, 11, 15], target = 9,Because nums[0] + nums[1] = 2 + 7 = 9, return [0, 1].

?

程序代碼：

#include <gtest/gtest.h> #include <map> #include <vector> #include <algorithm> using namespace std;// 暴力遍歷 vector<int> twoSum1(vector<int>& nums, int target) {vector<int> results;for (int i=0; i< nums.size(); ++i){for (int j=i+1; j < nums.size(); ++j){if (nums[i]+nums[j] == target){results.push_back(i);results.push_back(j);break;}}}return results; };// 緩存映射 vector<int> twoSum2(vector<int>& nums, int target) {vector<int> results;map<int, vector<int> > cache;bool find = false;for (unsigned int i=0; i<nums.size(); ++i){ cache[nums[i]].push_back(i); }for (unsigned int i=0; i<nums.size(); ++i){map<int, vector<int> >::const_iterator it = cache.find(target-nums[i]);if (it != cache.end()){for (unsigned int j = 0; j< it->second.size(); ++j){if (i != it->second[j]){results.push_back(i);results.push_back(it->second[j]);find = true;break;}}if (find){break;}}}return results; };// 排序后查找 struct Node {int index;int value;Node(int i, int v){index = i;value = v;}bool operator < (Node& ref){return value < ref.value;} };vector<int> twoSum(vector<int> &nums, int target) {vector<int> results;vector<Node> cache;for (int i=0; i<nums.size(); ++i){cache.push_back(Node(i, nums[i]));}sort(cache.begin(), cache.end());for (int i = 0, j = cache.size() - 1; i < j;){int value = cache[i].value + cache[j].value;if (value == target){results.push_back(min(cache[i].index, cache[j].index));results.push_back(max(cache[i].index, cache[j].index));break;}else if (value > target){--j;}else{++i;}}return results; };TEST(Pratices, tTwoSum) {// [3, 3, 1, 2] 3 => [0, 1]// [2, 7, 11, 15] 9 => [0, 1]// [-1, 8, 10, 12, 40, 11] 10 => [0,5] vector<int> data;data.push_back(3);data.push_back(3);data.push_back(1); data.push_back(2); vector<int> results = twoSum(data,6);data.clear();data.push_back(2);data.push_back(7);data.push_back(11);data.push_back(15);results = twoSum(data,9);data.clear();data.push_back(-1);data.push_back(8);data.push_back(10);data.push_back(12);data.push_back(40);data.push_back(11);results = twoSum(data,10); }

轉載于:https://www.cnblogs.com/Quincy/p/5212794.html

《新程序員》：云原生和全面數字化實踐50位技術專家共同創作，文字、視頻、音頻交互閱讀

總結

以上是生活随笔為你收集整理的[算法练习]Two Sum的全部內容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網站內容還不錯，歡迎將生活随笔推薦給好友。