Added 1669B - Triple.cpp

Author: vikashpatel24

1669B - Triple.cpp

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+//                                 ॐ नमः शिवाय
+#include<bits/stdc++.h>
+using namespace std;
+#define ll long long
+ 
+// Code Written By: Vikash Patel
+// Codeforces Profile: https://codeforces.com/profile/vikashpatel
+
+
+int solve(int a[], int n)
+{
+    unordered_map<int, int> ump;
+    for(int i=0;i<n;i++)
+    {
+        ump[a[i]]++;
+        if(ump[a[i]]==3)
+        return a[i];
+    }
+    return -1;
+}
+int main()
+{
+    int t;
+    cin>>t;
+    while(t--)
+    {
+        int n;
+        cin>>n;
+        int a[n];
+        for(int i=0; i<n; i++)
+        {
+            cin>>a[i];
+        }
+        cout<<solve(a,n)<<endl;
+    }
+    return 0;
+}