Package g1801_1900.s1857_largest_color_value_in_a_directed_graph

Class Solution

  • All Implemented Interfaces:
    
public final class Solution

    1857 - Largest Color Value in a Directed Graph.

    Hard

    There is a directed graph of n colored nodes and m edges. The nodes are numbered from 0 to n - 1.

    You are given a string colors where colors[i] is a lowercase English letter representing the color of the <code>i<sup>th</sup></code> node in this graph ( 0-indexed ). You are also given a 2D array edges where <code>edgesj = a<sub>j</sub>, b<sub>j</sub></code> indicates that there is a directed edge from node <code>a<sub>j</sub></code> to node <code>b<sub>j</sub></code>.

    A valid path in the graph is a sequence of nodes <code>x<sub>1</sub> -> x<sub>2</sub> -> x<sub>3</sub> -> ... -> x<sub>k</sub></code> such that there is a directed edge from <code>x<sub>i</sub></code> to <code>x<sub>i+1</sub></code> for every 1 &lt;= i &lt; k. The color value of the path is the number of nodes that are colored the most frequently occurring color along that path.

    Return the largest color value of any valid path in the given graph, or -1 if the graph contains a cycle.

    Example 1:

    Input: colors = "abaca", edges = [0,1,0,2,2,3,3,4]

    Output: 3

    Explanation: The path 0 -> 2 -> 3 -> 4 contains 3 nodes that are colored "a" (red in the above image).

    Example 2:

    Input: colors = "a", edges = [0,0]

    Output: -1

    Explanation: There is a cycle from 0 to 0.

    Constraints:

    • n == colors.length

    • m == edges.length

    • <code>1 <= n <= 10<sup>5</sup></code>

    • <code>0 <= m <= 10<sup>5</sup></code>

    • colors consists of lowercase English letters.

    • <code>0 <= a<sub>j</sub>, b<sub>j</sub>< n</code>

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description

    • Field Summary

      Fields 
      Modifier and Type Field Description

    • Constructor Summary

      Constructors 
      Constructor Description
      Solution()

    • Enum Constant Summary

      Enum Constants 
      Enum Constant Description

    • Method Summary

      Modifier and Type Method Description
      final Integer largestPathValue(String colors, Array<IntArray> edges)

      • Methods inherited from class java.lang.Object

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