A little experience about writing questions on LeetCode for the first time

Although I am a student majoring in computer science, I have been busy with professional courses before, and I have not been able to really use these good programming websites to improve my algorithmic ability. After two years of college life, in the last year, I hope that I The programming ability has improved after going out for an internship, so I decided to write questions on the programming website in the future to improve my ability. I didn't expect that the first time I brushed the questions, I encountered a bottleneck. The question, I thought the right way, but I failed to write the code correctly. Then I copied other people's code in the discussion and ran it, and there was an error. Then I kept looking for the answer on the Internet, and finally solved this simple problem. Suddenly I feel that I am white. I have learned professional knowledge for two years, and writing this blog is just to remind myself that I should cherish the rest of my college time, otherwise I will really be eliminated. . . The title and code are attached below.

topic:

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].

Error analysis of the original code: that is, without adding class solution{} to enclose the core code inside.

Code:

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[j] == target - nums[i]) {
                return new int[] { i, j };
            }
        }
    }
    throw new IllegalArgumentException("No two sum solution");
}
}