CodePudding user response:

 # include & lt; Stdio. H> 
#include  

# define maxsize 100 

Typedef struct node {
Int stack [maxsize]; 
Int top; 
} Seqstack; 

Seqstack * initstack (Seqstack * s) 
{
S=(Seqstack *) malloc (sizeof (Seqstack)); 
if(! S) {
There is insufficient space on the printf (" \ n "); 
return NULL; 
} 
The else {s - & gt; Top=1; 
Return s; 
} 
} 
Push Seqstack * (Seqstack * s, int x) 
{
If (s - & gt; Top==maxsize - 1) 
{
Printf (" the stack is full \ n "); 
return NULL; } 
The else {
S - & gt; Top++; 
S - & gt; Stack [s - & gt; top]=x; 
Return s; 
} 
} 

Int pop (Seqstack * s) 
{if (s - & gt; Top==1) 
{
Printf (" empty stack \ n "); 
//return NULL;//why return NULL? 
return -1; 
} 
The else 
S - & gt; Top -; 
The return of s - & gt; Stack [s - & gt; top + 1]; 
} 
Void the display (Seqstack * s) 
{
int i=0; 

If (s - & gt; Top==1) 
{
Printf (" empty stack \ n "); 
} 
The else {
While (I & lt; S - & gt; Top) 
{
//s - & gt; Top -; 
Printf (" % d - & gt;" That s - & gt; Stack [I]); 
i++; 
} 
} 
} 

//void main () 
Int main () 
{Seqstack * s, * p; 
int i; 
Int a [6]={3,5,7,2,9,16}; 
S=initstack (s); 
Printf (" stack, "); 
for(i=0; i<6; I++) 
S=push (s, a [I]); 
The display (s); 
Printf (" \ n stack: "); 
While (s - & gt; The top!=1) 
Printf (" % 4 d, "pop (s)); 
printf("\n"); 
}