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I'm trying to create a tree using C and print its tree traversals(preorder,inoreder,postorder) so i decided to start creating a tree first. My program accepts a characters in preorder but it doesn't print the data I entered. Could someone help me?

```
#include<stdio.h>
#define MAXNODES 26
void push();
void pop();
char TOP();
typedef struct node{
char n;
struct node*next;
}NODE;
NODE *T[MAXNODES];
NODE *S;
void create(){
NODE *p,*new,*q;
int i,s,r;
char m;
clrscr();
i=s=0;
printf("Enter nodes in preorder;");
m=getche();
while(m!='\n'){
if((m<48 || m>57) && (m<65 || m>90) && (m<97 || m>122))
m=getche();
else{
while (T[s]!=NULL)
s++;
new=(NODE*)malloc(sizeof(NODE));
if (new==NULL){
printf("List is full!");
getch();
return;
}
r=0;
do{
p=T[r];
q=p->next;
r++;
}while (r<MAXNODES && p!=NULL && p->n!=m);
if (r==MAXNODES) {
new->n=m;
T[s]=new;
new->next=NULL;
}
else
free(new);
if (i>=1){
new=(NODE*)malloc(sizeof(NODE));
if(new==NULL){
printf("List is full!");
getch();
return;
}
new->n=m;
p=q=T[s-i];
while (p!=NULL){
q=p;
p=p->next;
}
q->next=new;
new->next=NULL;
}
i++;
m=getche();
}
}
}
char leftmost_child(char m){
NODE*p,*q;
int i=0;
for (i=0;i<MAXNODES;i++){
p=q=T[i];
p=p->next;
if(p->n == m){
q=p->next;
if (q!=NULL)
return (q->n);
else
return ('');
}
}
}
char right_sibling(char m){
NODE *p,*q;
int i=0;
for(i=0;i<MAXNODES;i++){
p=q=T[i];
p=p->next;
if (p->n !=m && p->next!=NULL){
q=p->next;
while(q->n !=m && q!=NULL)
q=q->next;
if (q!=NULL){
if (q->next !=NULL)
return (q->n);
else
return ('');
}
}
}
}
char root(){
NODE*p,*q;
int i, j;
char m;
for(i=MAXNODES-1;i>=0;i--){
p=q=T[i];
p=p->next;
if (i!=0){
if (T[i]!=NULL && p->next!=NULL){
p=T[i];
p=p->next;
while (p->next !=NULL){
m=p->n;
q=T[j];
q=q->next;
j=0;
while (j<i && q->n !=m)
j++;
if (j<i)
return (p->n);
}
}
else{
p=T[i];
p=p->next;
if(T[i]!=NULL && p->next!=NULL)
return(p->n);
else
return('');
}
}
}
}
void preorder(){
char c;
S=NULL;
clrscr();
printf("PREORDER: ");
c=root();
while(1){
if (c!=''){
printf("%c",c);
push(c);
c=leftmost_child(c);
}
else{
if (S==NULL)
return;
c=right_sibling(TOP());
pop();
}
}
}
void push(char o){
NODE*new,*p;
p=S;
new=(NODE*)malloc(sizeof(NODE));
if(new==NULL){
printf("List is full!");
getch();
return;
}
new->n=o;
if(S==NULL){
S=new;
new->next=NULL;
}
else if(S!=NULL){
p=p->next;
S=new;
new->next=p;
}
}
void pop(){
NODE*p;
p=S;
if(S!=NULL){
p=p->next;
S=p->next;
free(p);
}
}
char TOP(){
NODE *t;
t=S;
if (S==NULL)
return;
else{
t=t->next;
return (t->n);
}
}
void makenull(){
int i=0;
for(i=0;i<MAXNODES;i++)
T[i]=NULL;
}
main(){
char ans='Y';
makenull();
while ((ans=='Y') || (ans=='y')) {
create();
clrscr();
printf("Enter another node?Y\N");
scanf("%c",&ans);
}
if(T!=NULL)
preorder();
getch();
}
```