Package g3501_3600.s3528_unit_conversion_i

Class Solution

  • All Implemented Interfaces:
    
public final class Solution

    3528 - Unit Conversion I.

    Medium

    There are n types of units indexed from 0 to n - 1. You are given a 2D integer array conversions of length n - 1, where <code>conversionsi = sourceUnit<sub>i</sub>, targetUnit<sub>i</sub>, conversionFactor<sub>i</sub></code>. This indicates that a single unit of type <code>sourceUnit<sub>i</sub></code> is equivalent to <code>conversionFactor<sub>i</sub></code> units of type <code>targetUnit<sub>i</sub></code>.

    Return an array baseUnitConversion of length n, where baseUnitConversion[i] is the number of units of type i equivalent to a single unit of type 0. Since the answer may be large, return each baseUnitConversion[i] modulo <code>10<sup>9</sup> + 7</code>.

    Example 1:

    Input: conversions = [0,1,2,1,2,3]

    Output: 1,2,6

    Explanation:

    • Convert a single unit of type 0 into 2 units of type 1 using conversions[0].

    • Convert a single unit of type 0 into 6 units of type 2 using conversions[0], then conversions[1].

    Example 2:

    Input: conversions = [0,1,2,0,2,3,1,3,4,1,4,5,2,5,2,4,6,3,5,7,4]

    Output: 1,2,3,8,10,6,30,24

    Explanation:

    • Convert a single unit of type 0 into 2 units of type 1 using conversions[0].

    • Convert a single unit of type 0 into 3 units of type 2 using conversions[1].

    • Convert a single unit of type 0 into 8 units of type 3 using conversions[0], then conversions[2].

    • Convert a single unit of type 0 into 10 units of type 4 using conversions[0], then conversions[3].

    • Convert a single unit of type 0 into 6 units of type 5 using conversions[1], then conversions[4].

    • Convert a single unit of type 0 into 30 units of type 6 using conversions[0], conversions[3], then conversions[5].

    • Convert a single unit of type 0 into 24 units of type 7 using conversions[1], conversions[4], then conversions[6].

    Constraints:

    • <code>2 <= n <= 10<sup>5</sup></code>

    • conversions.length == n - 1

    • <code>0 <= sourceUnit<sub>i</sub>, targetUnit<sub>i</sub>< n</code>

    • <code>1 <= conversionFactor<sub>i</sub><= 10<sup>9</sup></code>

    • It is guaranteed that unit 0 can be converted into any other unit through a unique combination of conversions without using any conversions in the opposite direction.

    • 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 IntArray baseUnitConversions(Array<IntArray> conversions)

      • Methods inherited from class java.lang.Object

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