Package g1101_1200.s1128_number_of_equivalent_domino_pairs

Class Solution

java.lang.Object

g1101_1200.s1128_number_of_equivalent_domino_pairs.Solution

public class Solution
extends Object

1128 - Number of Equivalent Domino Pairs.

Easy

Given a list of dominoes, dominoes[i] = [a, b] is equivalent to dominoes[j] = [c, d] if and only if either (a == c and b == d), or (a == d and b == c) - that is, one domino can be rotated to be equal to another domino.

Return the number of pairs (i, j) for which 0 <= i < j < dominoes.length, and dominoes[i] is equivalent to dominoes[j].

Example 1:

Input: dominoes = [[1,2],[2,1],[3,4],[5,6]]

Output: 1

Example 2:

Input: dominoes = [[1,2],[1,2],[1,1],[1,2],[2,2]]

Output: 3

Constraints:

• 1 <= dominoes.length <= 4 * 104
• dominoes[i].length == 2
• 1 <= dominoes[i][j] <= 9

Constructor Summary

Constructors

Constructor	Description
Solution()

Method Summary

Modifier and Type	Method	Description
int	numEquivDominoPairs(int[][] dominoes)

Methods inherited from class java.lang.Object

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

Constructor Detail

Solution

public Solution()

Method Detail

numEquivDominoPairs

public int numEquivDominoPairs(int[][] dominoes)