用java解决LeetCode(1)——Two Sum

问题：
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].
方案：

public class Solution {
    public int[] twoSum(int[] nums, int target) {
        for(int i=0;i<nums.length;i++)
          for(int j=i+1;j<nums.length;j++)
          {
              if(nums[i]+nums[j]==target)
              return new int[]{i,j};
          }
          return null;
    }
}

方法比较简单，适合初学者。