1. Submit THREE files for each problem (DO NOT ZIP): 
 a. your source code in Leetcode saved as Solution-278.java
 b. a screen snap showing your submission history and user account
 c. a screen snap showing the runtime of your best submission and user account

2. Edit this head and add it to your every source code. 
/*
  Course: CSCI 230
  Name: Your Name
  Homework Assignment 1
  Problem 1.1: Leetcode 278 - First Bad Version
  Data Structure and Algorithm: Binary Search
*/

3. Grading Policy. 
- Full credit for submitting by deadline with 100% correctness and passing all testing cases.
- Half credit for minor inperfection (e.g. failing a large testing case) or minor delay (typically in hours).
- Zero credit for major error(s) or severe delay.