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].

給定一個整數數組和一個目標值，找出數組中和為目標值的兩個數。

你可以假設每個輸入只對應一種答案，且同樣的元素不能被重復利用。

示例:

給定 nums = [2, 7, 11, 15], target = 9

因為 nums[0] + nums[1] = 2 + 7 = 9
所以返回 [0, 1]

 1 class Solution {
 2     func twoSum(_ nums: [Int], _ target: Int) -> [Int] {
 3         //創建一個初始化數據為空的數組用於返回
 4         var targetArray:[Int]=[Int]()
 
 5         //獲取數組長度，減2用於遍歷數組,註意最後一個的情況
 6         for addIndex1 in 0...nums.count-2
 7         {
 8             //該值之後向後遍歷，不支持運算符<..
 9             for addIndex2 in (addIndex1+1)...nums.count-1
10             {
11                 if(nums[addIndex1]+nums[addIndex2]==target)
12                 {
13                     targetArray.append(addIndex1)
 
14                     targetArray.append(addIndex2)
15                     break                   
16                 }               
17             }
18         }
19         return targetArray
20     }
21 }

LeetCode：Two Sum