Can we increment in printf?

There is no strict rule about incrementing variables inside of printf() . You don’t need to do this, but it is very valuable operation, worth knowing. ++k is called pre-incrementation: value of k will be incremented first, then used.

Where is the implementation of printf?

Printf and scanf are most frequently used in any programs written with C language. These functions implicitly work on console stdin/stdout files. There are other variations of these functions. fprintf/fscanf operates on file buffer and sscanf/sprintf can operates on string buffer.

How many times printf is executed?

Answer is NEVER . It means the pointer will never reach inside the LOOP. This is major cause of the PrintF command will never RUN in this program.

What is the first argument of printf?

text string
C Program 2.1 contains a printf() statement with only one argument, that is, a text string. This string is referred to as the message string and is always the first argument of printf().

What is prototype for printf?

The prototype of printf() is: int printf(char *format, arg1, arg2.); printf converts, formats, and prints its arguments on the standard output. It returns the number of characters printed. The format string contains two different types of things: 1.

What is the first argument of printf where it is stored?

In the most simple case, printf takes one argument: a string of characters to be printed. This string is composed of characters, each of which is printed ex- actly as it appears.

What is printf should have a prototype?

What is meant by prototype error in printf? – Quora. Whenever there is a prototype error, it means that you have not included the header file which has a particular predefined function that is being used in the program. And the missing prototype is

How does printf identify the number of arguments passed?

The printf function uses its first argument to determine how many arguments will follow and of what types they are. If you don’t use enough arguments or if they are of the wrong type than printf will get confuses, with as a result wrong answers.

What is the Order in which printf arguments are evaluated?

Function arguments are evaluated in an unspecified order. This allows the compiler to optimize however it likes. Your particular arguments invoke undefined behavior. You’re not allowed to modify i multiple times before a sequence point. The evaluation order of printf arguments is unspecified.

How to guess what will be the output of printf()?

Now we will try to guess what will be the output. Most of the compilers takes each parameter of printf () from right to left. So in the first printf () statement, the last parameter is x++, so this will be executed first, it will print 20, after that increase the value from 20 to 21. Now print the second last argument, and show 21.

What is the Order of evaluation of the function parameters?

The evaluation order of function parameters is unspecified. 10/ The order of evaluation of the function designator, the actual arguments, and subexpressions within the actual arguments is unspecified, but there is a sequence point before the actual call. This is, however, only a part of the problem.

How to get 21 from 20 in C++ printf?

So in the first printf () statement, the last parameter is x++, so this will be executed first, it will print 20, after that increase the value from 20 to 21. Now print the second last argument, and show 21. Like that other lines are also calculated in this manner.