problem with Structs/NULL

This is a discussion on problem with Structs/NULL within the C Programming forums, part of the General Programming Boards category; For an assignment, we have to use hashing to insert a dictionary(an array of linked lists) but I seem to ...

  1. #1
    Registered User
    Join Date
    Jan 2003
    Posts
    36

    problem with Structs/NULL

    For an assignment, we have to use hashing to insert a dictionary(an array of linked lists) but I seem to be unable to set any of them to NULL.

    btw: note this is my first C program, I learned to program entirely in Java prior to this.

    Code:
    #include<stdio.h>
    #include<stdlib.h>
    #include<string.h>
    
    #define WORDSIZE 32
    #define TABLESIZE 2000
    #define HASH_VALUE 13
    
    int tablePosition;
    struct LIST table[TABLESIZE];		//table
    
    //global methods
    int hash(char string[]);
    
    
    struct NODE
    {
    	char word[WORDSIZE];
    	struct NODE *next;
    };
    
    struct LIST
    {
    	struct NODE listTop;
    };
    
    struct QUEUE
    {
    	struct NODE queueTop;
    	struct NODE queueBottom;
    }queue;
    
    int main(int argc, char *argv[])
    {
    
    	int i;
    	int arg;
    	char string[WORDSIZE];
    	FILE* word;
    
    	{
    		void insert();
    	}
    
    	arg=getopt(argc,argv,"d:");
    
    	if(-1!=arg)
    		word = fopen(optarg,"r");
    	else
    	printf("OOPS");
    
    
    	//sets the first character in each list to NULL to check for empty lists
    	for(i=0;i<TABLESIZE;i++)
    		table[i].listTop.word=NULL;
    
    	while(fgets(string,WORDSIZE,word))
    	{
    printf("%s",string);
    //		insert(string);
    	}
    
    
    
    
    	fclose(word);
    	return EXIT_SUCCESS;
    }


    Code tags added by Hammer

  2. #2
    End Of Line Hammer's Avatar
    Join Date
    Apr 2002
    Posts
    6,231
    >>table[i].listTop.word=NULL
    make it
    >>table[i].listTop.word[0] = '\0'
    When all else fails, read the instructions.
    If you're posting code, use code tags: [code] /* insert code here */ [/code]

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