%s is the output string.

%d is an output integer.

%f is an output integer.

This is an escape identifier used in functions such as scanf and printf to map parameter types to corresponding positions in input/output statements.

Where% c- corresponding character char% s- corresponding character string char *(char[])% d- corresponding integer int% LD- corresponding long integer% x- corresponding hexadecimal integer, lowercase letter% x is greater than 9- corresponding hexadecimal integer, and uppercase letter% u is greater than 9- corresponding unsigned integer.

C language is a process-oriented computer programming language, which is different from object-oriented programming languages such as C++ and Java.

Its compilers mainly include Clang, GCC, WIN-TC, SUBLIME, MSVC, Turbo C and so on.

Extended data:

Integer type: (i.e. number) output integer d%

Floating-point type, also called real number type (decimal) %f, exponent% e% g.

Characters (letters) output a character %c string %s

%d %f %e %g %c %s ... These are all control characters, which are usually used to output statements.

As for escape characters, they are usually backslashes ('\') and corresponding identifiers, such as the required output line break' \n'

The statement printf("ABCDEF\n ") automatically switches to the next line after outputting ABCDEF, and' \n' will not be displayed on the screen, that is to say, escape characters will not be displayed when used in the output statement.

\ a bell \ b backspace \ f pagefeed \ n linefeed \ r carriage return \ t horizontal tab \v vertical tab \0 null character.

K & ampR C mainly introduces the following features:

structure type

Long integer

Unsigned int type

Change the operators =+and =-to+= and-=. Because =+and =-will make the compiler not know whether the user wants to process i =-10 or i =- 10, which will cause confusion in processing.

Even years after the ANSI C standard was put forward, K&; R C is still the most accurate requirement of many compilers, and many old compilers still run K &；; Standard for reinforced concrete.

The data types of C include integer type, character type, real number type or floating point type (single precision and double precision), enumeration type, array type, structure type, * * * * object type, pointer type and null type.

C language keywords defined by ISO standard ***32:

Automatic double int structure interrupt else long switch

Case enumeration register typedef char extern returns union.

const float short unsigned continue for signed void

Default goto sizeof volatile do if when static inlining.

restrict _ Bool _ Complex _ Imaginary _ Generic？

References:

Baidu encyclopedia -C language