C语言简易文法

<program> ：

external_declaration

| program external_declaration

 

<external_declaration> ：      //外部声明

function_definition

| declaration

 

<type_specifier> ：    //类型

Void

|char

|int

|float

|double

<iteration_statement>:  //循环

|while '(' expression ')' statement

| for '(' expression_statement expression_statement ')' statement

 

<identifier>  ：    //标识符 头文件

Include

| define

|stdio.h

|math.h

|stdlib.h

|time.h

|string.h

|main ‘(‘ ‘)

 

 

<statement>  ：     //声明

 

udge_statement

 

|jump_statement

 

|iteration_statement

 

|selection_statement

 

<Judge_statement>  ：   //判断

selection_statement

: if '(' expression ')' statement

|if'(' expression ')' statement ELSE statement

 

 

| logical_or_expression '?' expression ':' conditional_expression

 

constant_expression ： //条件

 conditional_expression