chore: add greetings! program

Greetings!/main.cpp

@@ -0,0 +1,17 @@
+#include <iostream>
+#include <string>
+using namespace std;
+
+int main(){
+    string greeting = "";
+    cin >> greeting;
+    int length = greeting.length() - 2;
+    cout << "h";
+    for (int x = 0; x<length * 2; ++x)
+    {
+        cout << "e";
+    }
+    cout << "y" << endl;
+    
+    return 0;
+}