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Treesort [string array]



Treesort [string array]

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

struct tnode { 
 char *str;
 struct tnode *left; 
 struct tnode *right; 
};

void insert(struct tnode **p, char *value);
void print(struct tnode *root);

int main(void) {
 char line[1024];
 struct tnode *root;

 root = NULL;
 while((fgets(line, 1024, stdin)) != NULL)
  insert(&root, line);

 print(root);
 return 0;
}

/* call by reference .. ! */
void insert(struct tnode **p, char *value) {
 if(!*p) {
  *p = (struct tnode *)malloc(sizeof(struct tnode));
  (*p)->left = (*p)->right = NULL;
  (*p)->str = strdup(value);
  return;
 }

 if(strcmp(value, (*p)->str) < 0)
  insert(&(*p)->left, value);
 else 
  insert(&(*p)->right, value);
}
 
/* inorder binary tree print ... */
void print(struct tnode *root) {
 if(root != NULL) {
  print(root->left);
  printf("%s", root->str); 
  print(root->right);
 }
}