In this program, we are casting the operator to integer, So it is printing as 21 and 10
Output:
$ g++ op5.cpp
$ a.out
21 10

Here the condition is false on conditional operator, so the b value is assigned to c.
Output:
$ g++ op1.cpp
$ a.out
6

Because of the precedence the pre-increment and post increment operator, we got the output 

as 749736.
Output:
$ g++ op.cpp
$ a.out
749736

:j starts with the value 10. j is then incremented to 11. Next, j is added to 100. Finally, j 

(still containing 11) is added to 999 which yields the result 1010.
Output:
$ g++ op2.cpp
$ a.out
1010

It is a separtor here.In c,the value a is stored in c and in d the value b is stored in d because of 

the bracket.
Output:
$ g++ op3.cpp
$ a.out
5 6

 Because the dynamic_cast operator is used to convert from base class to derived class.

Because the * operator is having highest precedence, So it is executed first and then the + operator 

will be executed.
Output:
$ g++ op1.cpp
$ a.out
20

None

In this operator, if the condition is true means, it will return the first operator, otherwise second operator.

The operator which is having highest precedence is postfix and lowest is equality.