Create triplets.cpp

triplets.cpp

@@ -0,0 +1,33 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+// Function to print all triplets in
+// given sorted array that forms AP
+void printAllAPTriplets(int arr[], int n)
+{
+    unordered_set<int> s;
+    for (int i = 0; i < n - 1; i++)
+    {
+    for (int j = i + 1; j < n; j++)
+    {
+        // Use hash to find if there is
+        // a previous element with difference
+        // equal to arr[j] - arr[i]
+        int diff = arr[j] - arr[i];
+        if (s.find(arr[i] - diff) != s.end())
+            cout << arr[i] - diff << " " << arr[i]
+                 << " " << arr[j] << endl;
+    }
+    s.insert(arr[i]);
+    }
+}
+
+// Driver code
+int main()
+{
+    int arr[] = { 2, 6, 9, 12, 17,
+                 22, 31, 32, 35, 42 };
+    int n = sizeof(arr) / sizeof(arr[0]);
+    printAllAPTriplets(arr, n);
+    return 0;
+}