table.c

/*
 * table.c implements a <string,int> key/value data structure
 *
 * @author Dr. Fenwick
 * @version Fall 2014
 */

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

void initTable(tableType *Xtable)
{
    Xtable->numItemsInUse = 0;
}

/* When storing, it is necessary to check if the variable is already 
   present in the table.
   If it is, then rewrite the value as opposed to creating a completely 
   new entry.
*/
void store(tableType *Xtable, char *key, int val)
{
    int i;
    for(i = 0; i < Xtable->numItemsInUse; i++){
        //First pass through to see if value is already in the table.
        if(strcmp(key,Xtable->entry[i].key) == 0)
        {
            //If it is, overwrite the value and return
	        /* WRITE THIS STATEMENT */
            Xtable->entry[i].value = val;
            return;
        }
    }

    // If reach this point then the value is not already present, add it.
    /* WRITE CODE HERE */

    Xtable->entry[i].value = val;
    strcpy(Xtable->entry[i].key, key);
    Xtable->numItemsInUse++;
}

int retrieve(tableType *Xtable, char *key){
    //Search for entry. If found return value. If not, error occurred.
    /* WRITE CODE HERE */
    int i;
    for(i = 0; i < Xtable->numItemsInUse; i++)
    {
        if(strcmp(key, Xtable->entry[i].key) == 0)
        {
            return Xtable->entry[i].value;
        }
    }


    // Not found, report error.
    printf("ERROR, non-existant key %s in table.\n", key);
    exit(1);
    return 0; 
}

//for debugging
void printTable(tableType * Xtable)
{
    int i;
    for(i = 0; i < Xtable->numItemsInUse; i++)
    {
        printf("%s = %d\n", Xtable->entry[i].key, Xtable->entry[i].value);
    }
}