From 8ec04db6ab5448b2b977b8686f7bb6f6bf1a6df6 Mon Sep 17 00:00:00 2001
From: chayan das <dasshuvo817@gmail.com>
Date: Sun, 4 May 2025 17:11:17 +0530
Subject: [PATCH] Create 1128. Number of Equivalent Domino Pairs

---
 1128. Number of Equivalent Domino Pairs | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)
 create mode 100644 1128. Number of Equivalent Domino Pairs

diff --git a/1128. Number of Equivalent Domino Pairs b/1128. Number of Equivalent Domino Pairs
new file mode 100644
index 0000000..e5de742
--- /dev/null
+++ b/1128. Number of Equivalent Domino Pairs	
@@ -0,0 +1,19 @@
+class Solution {
+public:
+    int numEquivDominoPairs(vector<vector<int>>& dominoes) {
+        int n = dominoes.size();
+        map<vector<int>, int> m;
+        for(int i = 0; i < n; i++) {
+            sort(dominoes[i].begin(), dominoes[i].end());
+            m[dominoes[i]]++;
+        }
+        int sum = 0;
+        for(auto i : m) {
+            int count = i.second;
+            if(count > 1) {
+                sum += (count * (count - 1)) / 2;
+            }
+        }
+        return sum;
+    }
+};