C/stdio.h/printf

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Версия от 10:23, 25 мая 2010; Admin (обсуждение | вклад) (1 версия: Импорт контента...)
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31 non-null, automatically

  
#include <stdio.h>
int main( )
{
 char   psz2[]   =   "string text.";
 
 printf("%s",psz2); 
}


33 non-null, automatically

  
#include <stdio.h>
int main( )
{
 char   psz1[]   =   "this is a test";
 
 printf("%s",psz1); 
}


4 decimal places, left-justify

  
#include <stdio.h>
int main( )
{
 double dPi      =   3.14159265;
 
 printf("%-20.4f",dPi); 
}


decimal places, right-justify

  
#include <stdio.h>
int main( )
{
 double dPi      =   3.14159265;
 
 printf("%20.4f",dPi); 
}


default ivalue width, 4

  
#include <stdio.h>
int main( )
{
 int    ivalue   =   1234;
 
 printf("%d",ivalue); 
}


minimum 3 overridden, auto 4

  
#include <stdio.h>
int main( )
{
 int    ivalue   =   1234;
 
 printf("%3d",ivalue); 
}


minimum 5 overridden, auto 33

  
#include <stdio.h>
int main( )
{
 char   psz1[]   =   "this is a test";
 
 printf("%5s",psz1); 
}


minimum width 1

  
#include <stdio.h>
int main( )
{
 char c = "A";
 
 printf("%c",c); 
}


minimum width 10, left-justify

  
#include <stdio.h>
int main( )
{
 int    ivalue   =   1234;
 
 printf("%-d",ivalue); 
}


minimum width 10, right-justify

  
#include <stdio.h>
int main( )
{
 int    ivalue   =   1234;
 
 printf("%10d",ivalue); 
}


minimum width 19, print all 17

  
#include <stdio.h>
int main( )
{
 char   psz1[]   =   "this is a test";
 
 printf("%19.19s",psz1); 
}


minimum width 20, left-justify

  
#include <stdio.h>
int main( )
{
 double dPi      =   3.14159265;
 
 printf("%-20f",dPi); 
}


minimum width 20, right-justify

  
#include <stdio.h>
int main( )
{
 double dPi      =   3.14159265;
 
 printf("%20f",dPi); 
}


minimum width 38, left-justify

  
#include <stdio.h>
int main( )
{
 char   psz2[]   =   "string text.";
 
 printf("%-38s",psz2); 
}


minimum width 38, right-justify

  
#include <stdio.h>
int main( )
{
 char   psz1[]   =   "this is a test";
 
 printf("%38s",psz1); 
}


minimum width 5, left-justify

  
#include <stdio.h>
int main( )
{
 char c = "A";
 
 printf("%-5c",c); 
}


minimum width 5, right-justify

  
#include <stdio.h>
int main( )
{
 char c = "A";
 
 printf("%5c",c); 
}


Output char

  
#include <stdio.h>
int main( )
{
 char c = "A";
 
 printf("%c",c);
 
}


print character with ASCII 90

  
#include <stdio.h>
int main( )
{
 char c = "A";
 
 printf("%c",90); 
}


printf %10d, %10.f

  
#include <stdio.h>
int main()
{
   int y = 7, z = 35;
   long longVar = 98456;
   float floatVar =  8.8;
   char *phraseFour = "Formatted: ";
   printf("%s %5d %10d  %10.5f\n",phraseFour,y,z,floatVar);
   return 0;
}


printf %d for integer

  
#include <stdio.h>
int main()
{
   int x = 5;
   printf("%d\n",x);
   return 0;
}


printf: display message by format

    
//Header file:     #include <stdio.h>  
//Declaration:     int printf(const char *format, ...); 
//Return:          the number of characters actually printed. A negative value indicates failure. 
// The printf() Format Specifiers
    
//Code Format
//%a:  Hexadecimal output in the form 0xh.hhhhp+d (C99 only). 
//%A:  Hexadecimal output in the form 0Xh.hhhhP+d (C99 only). 
//%c:  Character. 
//%d:  Signed decimal integers. 
//%i:  Signed decimal integers. 
//%e:  Scientific notation (lowercase e). 
//%E:  Scientific notation (uppercase E). 
//%f:  Decimal floating point. 
//%F:  Decimal floating point (C99 only; produces uppercase INF, INFINITY, or NAN when applied to infinity or a value that is not a number. The %f specifier produces lowercase equivalents.) 
//%g:  Uses %e or %f, whichever is shorter. 
//%G:  Uses %E or %F, whichever is shorter. 
//%o:  Unsigned octal. 
//%s:  String of characters. 
//%u:  Unsigned decimal integers. 
//%x:  Unsigned hexadecimal (lowercase letters). 
//%X:  Unsigned hexadecimal (uppercase letters). 
//%p:  Displays a pointer. 
//%n:  The associated argument must be a pointer to an integer. This specifier causes the number of characters written (up to the point at which the %n is encountered) to be stored in that integer. 
//%%:  Prints a percent sign. 
  

#include <stdio.h>
int main(void){
 printf("Hi %c %d %s", "c", 10, "there!");
}

         
/*
Hi c 10 there!*/


printf ivalue with + sign

  
#include <stdio.h>
int main( )
{
 int    ivalue   =   1234;
 
 printf("%+d",ivalue); 
}


printf %ld for long integer number

  
#include <stdio.h>
int main()
{
   char *phraseTwo = "Here"s some values: ";
   char *phraseThree = " and also these: ";
   int y = 7, z = 35;
   long longVar = 98456;
   float floatVar =  8.8;
   printf("%s %d %d %s %ld %f\n",phraseTwo,y,z,phraseThree,longVar,floatVar);
   return 0;
}


printf %s for string

  
#include <stdio.h>
int main()
{
   printf("%s","hello world\n");
   char *phrase = "Hello again!\n";
   printf("%s",phrase);
   return 0;
}


print ivalue as octal value

  
#include <stdio.h>
int main( )
{
 int ivalue = 1234;
 
 printf("%o",ivalue); 
}


print lower-case hexadecimal

  
#include <stdio.h>
int main( )
{
 int ivalue = 1234;
 
 printf("%x",ivalue); 
}


prints 2 chars, left-justify

  
#include <stdio.h>
int main( )
{
 char   psz1[]   =   "this is a test",
        psz2[]   =   "string text.";
 
 printf("%-19.2s",psz1); 
}


prints 2 chars, right-justify

  
#include <stdio.h>
int main( )
{
 char   psz1[]   =   "this is a test";
 
 printf("%19.2s",psz1); 
}


prints first 2 chars

  
#include <stdio.h>
int main( )
{
 char   psz1[]   =   "this is a test";
 
 printf("%.2s",psz1); 
}


print the ASCII code for c

  
#include <stdio.h>
int main( )
{
 char c =   "A";
 
 printf("%d",c); 
}


print upper-case hexadecimal

  
#include <stdio.h>
int main( )
{
 int ivalue = 1234;
 
 printf("%X",ivalue); 
}


right-justify with leading 0"s

  
#include <stdio.h>
int main( )
{
 double dPi      =   3.14159265;
 
 printf("%020f",dPi); 
}


using default number of digits

  
#include <stdio.h>
int main( )
{
 double dPi      =   3.14159265;
 
 printf("%f",dPi); 
}


using printf arguments

  
#include <stdio.h>
int main( )
{
 char   psz1[]   =   "this is a test",
        psz2[]   =   "string text.";
 
 
 printf("%*.*s",19,6,psz1); 
}


width 10, 8 to right of "."

  
#include <stdio.h>
int main( )
{
 double dPi      =   3.14159265;
 
 printf("%10.8f",dPi); 
}


width 20, 2 to right-justify

  
#include <stdio.h>
int main( )
{
 double dPi      =   3.14159265;
 
 printf("%20.2f",dPi); 
}


width 20, scientific notation

  
#include <stdio.h>
int main( )
{
 double dPi      =   3.14159265;
 
 printf("%20.2e",dPi);
 
}