Difference between revisions of "Week 2"

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#include <stdio.h>
+
''#include <stdio.h>''
  
 
The hash tag (#) tells the compiler how to do things '''BEFORE''' compilation.
 
The hash tag (#) tells the compiler how to do things '''BEFORE''' compilation.
  
 
The include word brings in the code from inside <stdio.h>
 
The include word brings in the code from inside <stdio.h>

Revision as of 12:40, 19 May 2010

Reviewing IPC 144

The Question Mark Operator

c = a > b ? 100 : 200;

It replaces an if statement and is much faster. If a is greater than b then 100, else 200.

Please note: The types 100 and 200 must be the same type or else it will not work.

Function Calls

printf("%d  %d, b, b = b + 1);

It returns 21 21. Why? Some compilers stack the arguments and read the last argument first. Therefore, it would see b as 21 as well.

a = printf("%d  %d, b, b = b + 1);

printf("%d\n", a);

What is a?

6

printf returns the number of characters printed (scanf also returns the number of characters input - special note: scanf cannot return a number greater than the % symbols in your scanf statement).

A function must have one point of entry and one point of exit. Only one return statement per function.


#include <stdio.h>

The hash tag (#) tells the compiler how to do things BEFORE compilation.

The include word brings in the code from inside <stdio.h>