One: C language (data types and operators)

1#include <stdio.h>/*is a pre-processing command, its role is to inform the C compiler system in the C program before the formal compilation needs to do some preprocessing work. */2    intMain ()The /*c program executes the code in the main function, or it can be said that the main function is the only entry in the C language. */3 {4printf"I Love imooc!");/*See if the print statement here is correct*/  5     return 0;6}

Two: Data type

1 #include <stdio.h>2int  main ()3{4      int  age=;  /* define the age variable */5     printf (" I am%d this year!") \ n", age); 6     return 0 ;     7 }

C Language Support data types

Formatted output

　　　　

1#include <stdio.h>2 intMain () {3     intAge = -;4     floatHeight =1.85;5     CharUnit ='m';6printf"Xiao Ming is%d years old \ n", age);7printf"Xiao Ming's height%f%c\n", height, unit);8printf"Xiao Ming is now learning it technology on the Internet in MU class"); 9     return 0;Ten}

Defining constants

1#include <stdio.h>2 3 #definePocketmoney 10//defining constants and constant values4 intMain ()5 {6    //Pocketmoney = 12; //does Xiao Ming increase his pocket money privately? 7printf"Xiaoming got%d dollars in pocket money again today \ n", Pocketmoney);8     return 0; 9}　

Automatic conversion type

1#include <stdio.h>2 intMain ()3 {4     Charc ='a';5     intn = C;//Assign c to n6     floatf = C;//Assign c to f7     DoubleD = C;//Assign c to D8printf"%d\n", n);9printf"%f\n", f);Tenprintf"%lf\n", d); One     return 0;  A}

　　Forced conversions

 1  #include <stdio.h>2  int   Main ()  3  { 4  double  num = 2.5 ; //  5  printf ( " num is%d\n  , (int  )  NUM); Cast to int output 2  6  return  0  ;  7 } 

Three: operator

Note In the division operation:

If the two digits of the division are integers, then the result is an integer, the fractional part is omitted, such as 8/3 = 2, and two is a decimal , and The result is a decimal number, such as: 9.0/2 = 4.500000.

Take note of the remainder operation:

This operation is only suitable for two integers , such as: 10%3 = 1, while 10.0%3 is wrong; The post-op symbol depends on the symbol being modulo, such as (-10)%3 =-1; and 10% (-3) = 1.

Note: The C language does not have the exponentiation operator, nor can it use arithmetic symbols such as x,÷.

Assignment Operators

+ =,-=, *=,/=,%=

　　Comparison operators

　　logical operators

　　Trinocular operator

1#include <stdio.h>2 intMain ()3 {4     //define the money in the small pocket5     DoubleMoney = A     ; 6     //define the cost of a taxi home7     DoubleCost =11.5      ; 8printf"Small series can take a taxi home:"); 9     //Output y small series on a taxi home, output n Small series can not take a taxi homeTenprintf"%c", Money>cost?'y':'N'            ); One     return 0; A}

One: C language (data types and operators)