Package g2201_2300.s2280_minimum_lines_to_represent_a_line_chart

Class Solution

  • public class Solution
extends Object
    2280 - Minimum Lines to Represent a Line Chart.

    Medium

    You are given a 2D integer array stockPrices where stockPrices[i] = [dayi, pricei] indicates the price of the stock on day dayi is pricei. A line chart 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:

    Return the minimum number of lines needed to represent the line chart.

    Example 1:

    Input: stockPrices = [[1,7],[2,6],[3,5],[4,4],[5,4],[6,3],[7,2],[8,1]]

    Output: 3

    Explanation:

    The diagram above represents the input, with the X-axis representing the day and Y-axis representing the price.

    The following 3 lines can be drawn to represent the line chart:

    • Line 1 (in red) from (1,7) to (4,4) passing through (1,7), (2,6), (3,5), and (4,4).

    • Line 2 (in blue) from (4,4) to (5,4).

    • Line 3 (in green) from (5,4) to (8,1) passing through (5,4), (6,3), (7,2), and (8,1).

    It can be shown that it is not possible to represent the line chart using less than 3 lines.

    Example 2:

    Input: stockPrices = [[3,4],[1,2],[7,8],[2,3]]

    Output: 1

    Explanation: As shown in the diagram above, the line chart can be represented with a single line.

    Constraints:

    • 1 <= stockPrices.length <= 105
    • stockPrices[i].length == 2
    • 1 <= dayi, pricei <= 109
    • All dayi are distinct.

    • Constructor Detail

      • Solution

        public Solution()

    • Method Detail

      • minimumLines

        public int minimumLines​(int[][] stockPrices)