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diamond problem CPP(most asked in interview)

Diamond Problem in C++ 💎 Diamond Problem in C++ Explained 🔍 The Basic Scenario a. Suppose P is the base class. b. Class Q and R inherit from class P. c. Class S inherits from both Q and R. Now, if P has a member (like a function), and S tries to access it, ambiguity arises: should it use the version from Q or from R? ⚠️ Problem Code (Ambiguous Inheritance) #include <iostream> using namespace std; class A { public: void show() { cout << "A::show" << endl; } }; class B : public A { }; class C : public A { }; class D : public B, public C { }; int main() { D obj; obj.show(); // ❌ Error: request is ambiguous } ✅ How We Solve It C++ solves the diamond problem using virtual inheritance , which ensures only one shared copy of the base class. ✅ Solved Version Using Virtual Inheritance ...
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top 2 from table

SQL Query: Fetch Top 2 Records by Salary Fetch Top 2 Records from a Table 🧩 Problem Statement: You are given access to a table named Employees , which contains employee details. Your task is to write a query to fetch the top 2 records from the table based on their Salary in descending order. If two or more employees have the same salary, prioritize by EmployeeID in ascending order. 📋 Sample Input Table: Employees EmployeeID Name Department Salary 101 Abhay HR 60000 102 aditya IT 75000 103 Vivek Finance 72000 104 Shubham IT 75000 105 Pradeep HR 58000 ✅ Sample Output EmployeeID Name Department Salary 102 aditya IT 75000 104 Shubham IT 75000 💡 SQL Query (Approach 1 & 2)...
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  Vivek
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Diamond problem in CPP

  Diamond problem explained The basic scenario a . Suppose P is the base class. b .Class Q and R inherits from class P. c. Class S inherits from both Q and R. Now, if P  has a member (like a variable or function), and S  tries to access it, ambiguity arises: should it use the version inherited via Q  or the one via R ? CPP Program: #include <iostream> using namespace std; class A { public:     void show() { cout << "A::show" << endl; } }; class B : public A { }; class C : public A { }; class D : public B, public C { }; int main() {     D obj;     obj.show(); // ❌ Error: request is ambiguous     } How we will solve it: C++ solve this problem using virtual function which ensures that only one copy of the base class is shared. Solved : #include <iostream> using namespace std; class A { public:     void show() { cout << "A::show" << endl; } }; class B : virtual public A { }; class C ...
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Fetch Top 2 Records From Table

  Title:  Fetch Top 2 Records from a Table. Problem Statement :  You are given access to a table named Employees , which contains employee details. Your task is to write a query to fetch the top 2 records from the table based on their Salary in descending order . If two or more employees have the same salary, prioritize by EmployeeID in ascending order. Sample Input Table: Employees EmployeeID Name  Department Salary 101        Abhay    HR               60000 102       aditya    IT                      75000 103       Vivek         Finance           72000 104       Shubham    IT                      75000 105       Pradeep    H...
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