C: Difference between revisions
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Else-if allows for more than one possibility: | |||
if (''expression'') | |||
''statement1'' | |||
else if | |||
''statement2'' | |||
else if | |||
''statement2'' | |||
else | else | ||
''statement2'' | ''statement2'' |
Revision as of 21:28, 18 October 2010
... a programming language to follow B.
C is the core language of Unix and later GNU/Linux and the liberation of it's compiler software, gcc (the Gnu's alternative to the proprietary Unix C compiler (cc)), a foundation of the Free Software movement.
Variables
Variables in C are strictly typed meaning they always are one particular kind of representation of information (an integer number, a character, a string of text).
- char
- int
- float
- double
int i = 0;
printf("%d\n", i);
(short and long are "qualifiers" that then can be used before the word in as in:
short int foo;
long int bar;
In these cases the word int can be left out.)
Strings
Strings in C are arrays of characters.
char text[] = "pioneering jazz electronic organ recordings";
int textlen = strlen(text);
printf("%s id %d chars long, and starts with %c\n", text, textlen, text[0]);
Abstractly a string in C is simply a pointer; that is, a numeric memory location pointing to the first character of the text in the memory.
Loops
Like, Bash, C has a for loop:
int i;
for (i=0; i<10; i++) {
printf("Hello %d\n", i);
}
If-Else
if (expression) statement1 else statement2
Else-if allows for more than one possibility:
if (expression) statement1 else if statement2 else if statement2 else statement2