I. History
1. C was originally designed for and implemented on the (what) operating system on the DEC PDP-11, by (who) .
2. The most recently approved ANSI/ISO C standard was issued in (when) , and single line comments notation “//” is or isn’t a feature of C89.
II. Syntax and Semantics
1. In a runtime C program, auto variables are stored in , static variables are stored in , and function parameters are stored in .
a. stack b. heap c. neither stack nor heap
2. The statement “extern int x;” is a , and the keyword extern is used during .
a. variable declaration b. variable definition
c. compilation time d. runtime
3. There is a complicated declaration: void ( * signal (int, void (*)(int)) ) (int);
If a statement “typedef void (*p) (int);” is given, please rewrite this complicated declaration.
4. The following code is a segment of C program.
……….
void func(int *p)
{………..}
……….
main()
{
int num=0;
………
func(&num);
……..
}
……….
Here, the function argument “&num” is passed .
a. by value b. by reference
III. Practice
Create a tree, which has h (h>0) layers, and its each node has w (w>0) sub-nodes.
Please complete the following incomplete solution.
#include <stdlib.h>
#include <string.h>
struct tree{
char info;
p_sub; //link to sub-nodes
};
// allocate memory and initiate
void dnode ( struct tree* tmp )
{
= malloc( sizeof (struct tree) );
= 0x41;
= NULL;
}
struct tree *dtree (struct tree* subtree, int height, int width)
{
int i;
if ( !subtree ) //if necessary, allocte memory for subtree
denode(subtree);
if ( height == 1 )
return subtree;
else if ( height == 2 ) {
struct tree *leaf = NULL;
for ( i=0; i<width; i++ ) {
denode ( );
;
leaf = NULL;
}
return subtree;
}
else {
for ( i=0; i<width; i++ ) {
}
return subtree;
}
}
main()
{
………
struct tree *root = NULL;
root = dtree (root, h, w) ; // h and w are integers get from input
………
}
