Raghavendra Ponde

finally block will execute i will give you one example imagine while doing exception handling programs if i am doing file handling if the file to which i am pointing is not there then it will thrown an exception if file is there it will not but i dont know whether file is there or not so i have to close connection or pointer with file.close().In catch() block also thinking that exception will come i have to write file.close() and also in try block also i have to write file.close() so i dont want to write it two times if i put in finally block then whether exception comes or not the required file will be closed after run time execution .

When do you absolutely have to declare a class as abstract (as opposed to free-willed educated choice or decision based on UML diagram)?

Imagine you have some set of inter related classes like mango , apple ,banana all these classes are having same functionality so instead of creating again repeated methods in these classes i will create a more generalized method fruits and in that i define the idea means how to do it and later on sub classes will implement those ideas so in a company many people will work for 2 or 3 years and leave the company we cant take the code of them what they have written i mean to say in projects many people mainly project managers create abstract classes and later on sub ordinates will use or override the function of that idea which is present in abstract class like that it works.when project are very big we just modify the code in abstract class it will automatically modified in sub class it is like kind of relationship eg : mango is kind of fruit like that and once i declare a class abstract i have to override it if i declare it virtual then it is upto me to override or not .Now coming to interface when classes are not related like cycle , train , bus means bus is belonging to automobile class and cycle to some other class but these different classes want to implement common functionality then interface is used and it is used to overcome the draw back of multiple inheritance as i can implement multiple interfaces and there is another drawback in inheritance using base class object i cannot call the sub class function to overcome that abstract classes are used .Try this stuff using code you will understand better thank you

Imagine you have some set of inter related classes like mango , apple ,banana all these classes are having same functionality so instead of creating again repeated methods in these classes i will create a more generalized method fruits and in that i define the idea means how to do it and later on sub classes will implement those ideas so in a company many people will work for 2 or 3 years and leave the company we cant take the code of them what they have written i mean to say in projects many people mainly project managers create abstract classes and later on sub ordinates will use or override the function of that idea which is present in abstract class like that it works.when project are very big we just modify the code in abstract class it will automatically modified in sub class it is like kind of relationship eg : mango is kind of fruit like that

there are four things for input getchar() ,getche(),gets() and getch() .echo means entering some input and confirmation means pressing enter key to see the output so when after wrting program you want the result without echo and confirmation then for that reason you write getch() at the end of program .when i am irerating in the loop i want to ask a question or take some input i will use getche() over there instead of getchar because it is without echo and with confirmation these things require demos live hope you understood some what

c and c++ are system languages which are very much near to hardware and it can make an hardware to run and it is difficult to write a system program .you can see drivers etc code will be written in c and c++ only so when a bug comes in system programming system itself will show you an error but when you go higher programming languages like java C# you have tester for them here no tester and c is procedural oriented language which acts as base for improving your programming skill and coding skill and c++ is partially object oriented as main function can be written outside where in C# every thing has to be encapsulated in class only .With C# and Java we call them application oriented languages as applications can be developed and c++ and c can be used in embedded systems for any product development as well Thank you