Asked to write component in react to handle forms

1st technical round:- Daily tasks, Const vs const expression, Encapsulation vs abstraction, Diamond problem how solved in C++, C++11 things, Undefined behavior, Dangling pointer, Inline function, Struct vs Class, Lambda expression, String sssaaxyz print first unique char which is 'x', Smart pointers, Oops 4 pillars encapsulation, polymorphism, abstraction, inheritance with example, R value references, Shallow copy vs deep copy, Unit test vs integration test, What is assert.