rbt rbt_insert(rbt r,char *s)
{
if(r == NULL){/*empty tree*/
r = emalloc(sizeof *r);
r->key = emalloc(strlen(s) * sizeof s[0] + 1);
r->colour = RED;
strcpy(r->key,s);
}else if(strcmp(r->key,s)==0){/*do nothing*/
}else if(strcmp(r->key,s) < 0){/*s > b-key */
r->right = rbt_insert(r->right,s);
}
else if(strcmp(r->key,s) > 0){/*s < b-key*/
r->left = rbt_insert(r->left,s);
}
r = rbt_fix(r);
return r;
}
rbt rbt_insert(rbt r, char *s) {
if (NULL == r) {
r = emalloc(sizeof *r);
r->key = emalloc(strlen(s) + 1);
r->colour = RED;
r->left = NULL;
r->right = NULL;
strcpy(r->key, s);
} else if (strcmp(s, r->key) == 0) {
/* do nothing */
} else if (strcmp(s, r->key) < 0) {
r->left = rbt_insert(r->left, s);
} else {
r->right = rbt_insert(r->right, s);
}
return rbt_fix(r);
}