Package g2101_2200.s2145_count_the_hidden_sequences

Class Solution

java.lang.Object

g2101_2200.s2145_count_the_hidden_sequences.Solution

public class Solution
extends Object

2145 - Count the Hidden Sequences.<p>Medium</p> <p>You are given a <strong>0-indexed</strong> array of <code>n</code> integers <code>differences</code>, which describes the <strong>differences</strong> between each pair of <strong>consecutive</strong> integers of a <strong>hidden</strong> sequence of length <code>(n + 1)</code>. More formally, call the hidden sequence <code>hidden</code>, then we have that <code>differences[i] = hidden[i + 1] - hidden[i]</code>.</p> <p>You are further given two integers <code>lower</code> and <code>upper</code> that describe the <strong>inclusive</strong> range of values <code>[lower, upper]</code> that the hidden sequence can contain.</p> <ul> <li>For example, given <code>differences = [1, -3, 4]</code>, <code>lower = 1</code>, <code>upper = 6</code>, the hidden sequence is a sequence of length <code>4</code> whose elements are in between <code>1</code> and <code>6</code> ( <strong>inclusive</strong> ). <ul> <li><code>[3, 4, 1, 5]</code> and <code>[4, 5, 2, 6]</code> are possible hidden sequences.</li> <li><code>[5, 6, 3, 7]</code> is not possible since it contains an element greater than <code>6</code>.</li> <li><code>[1, 2, 3, 4]</code> is not possible since the differences are not correct.</li> </ul> </li> </ul> <p>Return <em>the number of <strong>possible</strong> hidden sequences there are.</em> If there are no possible sequences, return <code>0</code>.</p> <p><strong>Example 1:</strong></p> <p><strong>Input:</strong> differences = [1,-3,4], lower = 1, upper = 6</p> <p><strong>Output:</strong> 2</p> <p><strong>Explanation:</strong> The possible hidden sequences are:</p> <ul> <li> <p>[3, 4, 1, 5]</p> </li> <li> <p>[4, 5, 2, 6]</p> </li> </ul> <p>Thus, we return 2.</p> <p><strong>Example 2:</strong></p> <p><strong>Input:</strong> differences = [3,-4,5,1,-2], lower = -4, upper = 5</p> <p><strong>Output:</strong> 4</p> <p><strong>Explanation:</strong> The possible hidden sequences are:</p> <ul> <li> <p>[-3, 0, -4, 1, 2, 0]</p> </li> <li> <p>[-2, 1, -3, 2, 3, 1]</p> </li> <li> <p>[-1, 2, -2, 3, 4, 2]</p> </li> <li> <p>[0, 3, -1, 4, 5, 3]</p> </li> </ul> <p>Thus, we return 4.</p> <p><strong>Example 3:</strong></p> <p><strong>Input:</strong> differences = [4,-7,2], lower = 3, upper = 6</p> <p><strong>Output:</strong> 0</p> <p><strong>Explanation:</strong> There are no possible hidden sequences. Thus, we return 0.</p> <p><strong>Constraints:</strong></p> <ul> <li><code>n == differences.length</code></li> <li><code>1 <= n <= 10⁵</code></li> <li><code>-10⁵ <= differences[i] <= 10⁵</code></li> <li><code>-10⁵ <= lower <= upper <= 10⁵</code></li> </ul>

Constructor Summary

Constructors

Constructor	Description
Solution()

Method Summary

Modifier and Type	Method	Description
int	numberOfArrays(int[] diff, int lower, int upper)

Methods inherited from class java.lang.Object

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

Constructor Details

Solution

public Solution()

Method Details

numberOfArrays

public int numberOfArrays(int[] diff,
 int lower,
 int upper)