Package g0201_0300.s0278_first_bad_version

Class VersionControl

java.lang.Object

g0201_0300.s0278_first_bad_version.VersionControl

Direct Known Subclasses:

Solution

public class VersionControl
extends Object

278 - First Bad Version.<p>Easy</p> <p>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.</p> <p>Suppose you have <code>n</code> versions <code>[1, 2, ..., n]</code> and you want to find out the first bad one, which causes all the following ones to be bad.</p> <p>You are given an API <code>bool isBadVersion(version)</code> which returns whether <code>version</code> is bad. Implement a function to find the first bad version. You should minimize the number of calls to the API.</p> <p><strong>Example 1:</strong></p> <p><strong>Input:</strong> n = 5, bad = 4</p> <p><strong>Output:</strong> 4</p> <p><strong>Explanation:</strong></p> <pre><code> call isBadVersion(3) -> false call isBadVersion(5) -> true call isBadVersion(4) -> true Then 4 is the first bad version. </code></pre> <p><strong>Example 2:</strong></p> <p><strong>Input:</strong> n = 1, bad = 1</p> <p><strong>Output:</strong> 1</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 <= bad <= n <= 2³¹ - 1</code></li> </ul>

Constructor Summary

Constructors

Constructor	Description
VersionControl(int bad)

Method Summary

Modifier and Type	Method	Description
boolean	isBadVersion(int version)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

VersionControl

public VersionControl(int bad)

Method Details

isBadVersion

public boolean isBadVersion(int version)