Package g2001_2100.s2001_number_of_pairs_of_interchangeable_rectangles

Class Solution

  • All Implemented Interfaces:
    
public final class Solution

    2001 - Number of Pairs of Interchangeable Rectangles.

    Medium

    You are given n rectangles represented by a 0-indexed 2D integer array rectangles, where <code>rectanglesi = width<sub>i</sub>, height<sub>i</sub></code> denotes the width and height of the <code>i<sup>th</sup></code> rectangle.

    Two rectangles i and j (i &lt; j) are considered interchangeable if they have the same width-to-height ratio. More formally, two rectangles are interchangeable if <code>width<sub>i</sub>/height<sub>i</sub> == width<sub>j</sub>/height<sub>j</sub></code> (using decimal division, not integer division).

    Return the number of pairs of interchangeable rectangles in rectangles.

    Example 1:

    Input: rectangles = [4,8,3,6,10,20,15,30]

    Output: 6

    Explanation: The following are the interchangeable pairs of rectangles by index (0-indexed):

    • Rectangle 0 with rectangle 1: 4/8 == 3/6.

    • Rectangle 0 with rectangle 2: 4/8 == 10/20.

    • Rectangle 0 with rectangle 3: 4/8 == 15/30.

    • Rectangle 1 with rectangle 2: 3/6 == 10/20.

    • Rectangle 1 with rectangle 3: 3/6 == 15/30.

    • Rectangle 2 with rectangle 3: 10/20 == 15/30.

    Example 2:

    Input: rectangles = [4,5,7,8]

    Output: 0

    Explanation: There are no interchangeable pairs of rectangles.

    Constraints:

    • n == rectangles.length

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

    • rectangles[i].length == 2

    • <code>1 <= width<sub>i</sub>, height<sub>i</sub><= 10<sup>5</sup></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 Long interchangeableRectangles(Array<IntArray> rec)

      • Methods inherited from class java.lang.Object

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