Solution (leetcode-in-java 1.19 API)

java.lang.Object
- g0201_0300.s0278_first_bad_version.VersionControl
- - g0201_0300.s0278_first_bad_version.Solution

```
public class Solution
extends VersionControl
```
278 - First Bad Version.
Easy

You are a product manager and currently leading a team to develop a new product. Unfortunately, the latest version of your product fails the quality check. Since each version is developed based on the previous version, all the versions after a bad version are also bad.

Suppose you have n versions [1, 2, ..., n] and you want to find out the first bad one, which causes all the following ones to be bad.

You are given an API bool isBadVersion(version) which returns whether version is bad. Implement a function to find the first bad version. You should minimize the number of calls to the API.

Example 1:

Input: n = 5, bad = 4

Output: 4

Explanation:
```
 call isBadVersion(3) -> false
 call isBadVersion(5) -> true
 call isBadVersion(4) -> true
 Then 4 is the first bad version. 
```
Example 2:

Input: n = 1, bad = 1

Output: 1

Constraints:
- 1 <= bad <= n <= 2³¹ - 1

- Constructor Summary
  
  Constructors
  Constructor Description
  
  Solution(int bad)
- Method Summary
  
  All Methods Instance Methods Concrete Methods
  Modifier and Type Method Description
  
  int firstBadVersion(int n)
  - Methods inherited from class g0201_0300.s0278_first_bad_version.VersionControl
    isBadVersion
  - Methods inherited from class java.lang.Object
    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail
- Solution
```
public Solution(int bad)
```

Method Detail
- firstBadVersion
```
public int firstBadVersion(int n)
```