Difference between revisions of "C функции"

From Ilianko
(Created page with " <code><pre> /************************************************************************ * * Purpose: Program to demonstrate passing a pointer to a scalar to * a function. ...")
 
 
(4 intermediate revisions by the same user not shown)
Line 1: Line 1:
 +
Предаване на стойност
 +
<code><pre>
 +
/************************************************************************
 +
*
 +
* Purpose: Program to demonstrate functions.
 +
* Author:  M J Leslie.
 +
* Date:    28-Feb-94
 +
*
 +
************************************************************************/
 +
 +
int add( int, int); /* Function declaration */
 +
 +
main()
 +
{
 +
  int i=1;
 +
  printf("i starts out life as %d.", i);
 +
 +
  i = add(1, 1); /* Function call      */
 +
 +
  printf(" And becomes %d after function is executed.\n", i);
 +
}
 +
 +
/************************************************************************/
  
 +
int add( int a, int b) /* Function definition */
 +
{
 +
  int c;
 +
  c = a + b;
 +
  return c;
 +
}
 +
</pre></code>
 +
 +
 +
Предаване на указател
 
<code><pre>
 
<code><pre>
 
/************************************************************************
 
/************************************************************************
Line 36: Line 69:
 
   return;
 
   return;
 
}
 
}
</code></pre>
+
</pre></code>
 +
 
 +
[[Category:C Справочник]]

Latest revision as of 12:23, 26 June 2012

Предаване на стойност

/************************************************************************
 *
 * Purpose: Program to demonstrate functions.
 * Author:  M J Leslie.
 * Date:    28-Feb-94
 *
 ************************************************************************/

int add( int, int); 			/* Function declaration 	*/

main()
{
  int i=1;
  printf("i starts out life as %d.", i);

  i = add(1, 1);			/* Function call       		*/

  printf(" And becomes %d after function is executed.\n", i);
}

/************************************************************************/

int add( int a, int b) 			/* Function definition 		*/
{
  int c;
  c = a + b;
  return c;
}


Предаване на указател

/************************************************************************
 *
 * Purpose: Program to demonstrate passing a pointer to a scalar to 
 *	    a function.
 * Author:  M J Leslie.
 * Date:    11-Apr-94
 *
 ************************************************************************/

void add(int*); 			/* Function declaration 	*/

main()
{
  int i=4;				/* variable declaration 	*/
  int* ptr;				/* int pointer			*/

  ptr = &i;				/* 'ptr' now contains the
					   address of 'i'		*/

  printf("i starts out life as %d.\n", i);
  printf("             *ptr is %d.\n", *ptr);

  add(ptr); 				/* Function call       		*/

  printf("            i is now %d.\n", i);
}

/************************************************************************/

void add(int *ptr)	 		/* Function definition 		*/
{
  ++*ptr;				/* Add 1 to the value
					 * pointed too by 'ptr'		*/
  return;
}