Java: First Bad Version

Difficulty Level: EASY

Problem Statement:

The problem "First Bad Version" is a classic binary search problem with a twist. You are given a function `isBadVersion(int version)` which returns whether a version is bad or not. Versions are numbered from 1 to n, and you need to find the first bad version. It is guaranteed that there is at least one bad version.

Input:

Suppose `n = 5`, and versions `[4, 5]` are bad according to the `isBadVersion()` function.

Output:

The first bad version is 4.