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1#include "HashTable.h"
2#include "WordEntry.h"
3#include <cstdlib>
4#include <list>
5
6/* HashTable constructor
7*  input s is the size of the array
8*  set s to be size
9*  initialize array of lists of WordEntry
10*/
11HashTable::HashTable (int s) : size(s){
12    hashTable = new list<WordEntry>[s];
13}
14
15/* computeHash
16*  return an integer based on the input string
17*  used for index into the array in hash table
18*  be sure to use the size of the array to 
19*  ensure array index doesn't go out of bounds
20*/
21// parameter s will be a word
22int HashTable::computeHash(const string &s) {
23    
24    int stringSize = s.size();
25    // string newS = s;
26    // char c = newS.at(0);
27    // int num = atoi(c);
28    return (s.size())  % size;
29}
30
31
32
33/* put
34*  input: string word and int score to be inserted
35*  First, look to see if word already exists in hash table
36*   if so, addNewAppearence with the score to the WordEntry
37*   if not, create a new Entry and push it on the list at the
38*   appropriate array index
39*/
40void HashTable::put(const string &s, int score) {
41    if(contains(s)){
42        // means string is in hash
43        
44        for(
45            list<WordEntry>:: iterator i = hashTable[computeHash(s)].begin(); 
46            i != hashTable[computeHash(s)].end(); 
47            ++i){
48            if (i->getWord() == s) {
49                i->addNewAppearance(score);
50                return;
51            }
52        }   	     
53	    
54	}else{
55	    WordEntry temp(s, score);
56	    hashTable[computeHash(s)].push_back(temp);
57	    return;
58	}
59}
60
61/* getAverage
62*  input: string word 
63*  output: the result of a call to getAverage()
64*          from the WordEntry
65*  Must first find the WordEntry in the hash table
66*  then return the average
67*  If not found, return the value 2.0 (neutral result)
68*/
69
70double HashTable::getAverage(const string &s) {
71    if (!contains(s)) {
72        return 2.0;
73    } else {
74        for (list<WordEntry>::iterator i = hashTable[computeHash(s)].begin(); 
75        i != hashTable[computeHash(s)].end(); ++i) {
76            if (i->getWord() == s){
77                return i->getAverage();
78            }
79        }        
80    }
81    
82}
83
84/* contains
85* input: string word
86* output: true if word is in the hash table
87*         false if word is not in the hash table
88*/
89bool HashTable::contains(const string &s) {
90    int num = computeHash(s);
91    
92    for (list<WordEntry>::iterator i = hashTable[num].begin(); i != hashTable[num].end(); ++i) {
93        if (i->getWord() == s){
94            return true;
95        }
96    }
97    return false;
98}