Package g2201_2300.s2280_minimum_lines_to_represent_a_line_chart

Class Solution

java.lang.Object
g2201_2300.s2280_minimum_lines_to_represent_a_line_chart.Solution
public class Solution extends Object
2280 - Minimum Lines to Represent a Line Chart.<p>Medium</p> <p>You are given a 2D integer array <code>stockPrices</code> where <code>stockPrices[i] = [day<sub>i</sub>, price<sub>i</sub>]</code> indicates the price of the stock on day <code>day<sub>i</sub></code> is <code>price<sub>i</sub></code>. A <strong>line chart</strong> is created from the array by plotting the points on an XY plane with the X-axis representing the day and the Y-axis representing the price and connecting adjacent points. One such example is shown below:</p> <p><img src="https://assets.leetcode.com/uploads/2022/03/30/1920px-pushkin_population_historysvg.png" alt="" /></p> <p>Return <em>the <strong>minimum number of lines</strong> needed to represent the line chart</em>.</p> <p><strong>Example 1:</strong></p> <p><img src="https://assets.leetcode.com/uploads/2022/03/30/ex0.png" alt="" /></p> <p><strong>Input:</strong> stockPrices = [[1,7],[2,6],[3,5],[4,4],[5,4],[6,3],[7,2],[8,1]]</p> <p><strong>Output:</strong> 3</p> <p><strong>Explanation:</strong></p> <p>The diagram above represents the input, with the X-axis representing the day and Y-axis representing the price.</p> <p>The following 3 lines can be drawn to represent the line chart:</p> <ul> <li> <p>Line 1 (in red) from (1,7) to (4,4) passing through (1,7), (2,6), (3,5), and (4,4).</p> </li> <li> <p>Line 2 (in blue) from (4,4) to (5,4).</p> </li> <li> <p>Line 3 (in green) from (5,4) to (8,1) passing through (5,4), (6,3), (7,2), and (8,1).</p> </li> </ul> <p>It can be shown that it is not possible to represent the line chart using less than 3 lines.</p> <p><strong>Example 2:</strong></p> <p><img src="https://assets.leetcode.com/uploads/2022/03/30/ex1.png" alt="" /></p> <p><strong>Input:</strong> stockPrices = [[3,4],[1,2],[7,8],[2,3]]</p> <p><strong>Output:</strong> 1</p> <p><strong>Explanation:</strong> As shown in the diagram above, the line chart can be represented with a single line.</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 <= stockPrices.length <= 10<sup>5</sup></code></li> <li><code>stockPrices[i].length == 2</code></li> <li><code>1 <= day<sub>i</sub>, price<sub>i</sub> <= 10<sup>9</sup></code></li> <li>All <code>day<sub>i</sub></code> are <strong>distinct</strong>.</li> </ul>

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • minimumLines

      public int minimumLines(int[][] stockPrices)