Binary Trees

Hi all,


I'm trying to do a binary search and collect some stats from a text
file in order to compare the processing times of this program (binary
searching) versus an old program using linked lists. I'm totally new
to binary searches by the way. Can anyone help me with the commented
sections below? Much of the code such as functions and printfs has
already been completed. Any help is greatly appreciated.


Thanks,
James

#include <stdio.h> 
#include <malloc.h> 
struct tnode {                  // specify the "shape" of a tnode structure ... 
        struct tnode *left;     // the left and right branch pointers 
        struct tnode *right; 
        int count;              // the word count as before 
        char *word;             // a pointer to the word 



} *root;                        // declare the root pointer variable 


struct tnode **tree_search(struct tnode **, char *); 
void tree_stats(struct tnode *); 
int get_word(char *); 

int total_nodes, total_words, high; 
struct tnode *most_frequent; 


int main(int argc, char *argv[]) { 
        struct tnode **tpp; 
        char word_buff[100];    // the reusable word buffer 
        int i; 
        while(get_word(word_buff)) { 
                tpp = tree_search(&root, word_buff); 
                /****CODE TO ADD NEW NODES AND COUNT REPEATS *****/ 


        } 
        tree_stats(root); 
        printf("total_nodes %d\n", total_nodes); 
        printf("total_words %d\n", total_words); 
        if(most_frequent) 
                printf("most frequent word <%s> count is %d\n", 
                        most_frequent->word, most_frequent->count); 
        for(i = 1; i < argc; i++) { 
                tpp = tree_search(&root, argv[i]); 
                if((*tpp) == NULL) 
                        printf("%s is NOT in the tree\n", argv[i]); 
                else 
                        printf("<%s> count is %d\n", argv[i], (*tpp)->count); 
        } 
        return(0); 



} 


// binary tree search returning a pointer to the pointer leading to a 
hit 
struct tnode **tree_search(struct tnode **tpp, char *w) { 
        /***** CODE TO DO THE BINARY SRCH *****/ 
        return(tpp); 


} 


// gather stats to check tree correctness 
void tree_stats(struct tnode *tp) { 
        /***** RECURSIVE CODE TO COLLECT ALL OF THE STATISTICS *****/ 


} 


#include <ctype.h> 
/* Leave this routine EXACTLY as it stands */ 
int get_word(char *s) { 
        int c; 
        do { 
                c = getchar(); 
                if(c == EOF) 
                        return(0); 
        } while(!isalpha(c) && !isdigit(c)); 
        do { 
                if(isupper(c)) 
                        c = tolower(c); 
                *s++ = c; 
                c = getchar(); 
        } while(isalpha(c) || isdigit(c)); 
        *s = 0; 
        return(1); 


}