// hashtable.cpp: implementation of the hashtable class.
//
//////////////////////////////////////////////////////////////////////


#include "hashtable.h"

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////


hashtable::hashtable(int size)
{
	hashTableSize = size;
	A = new value[size];
	for (int i=0;i<size;i++){
		A[i].word = "";
		A[i].num = 0;
	};
}


hashtable::~hashtable()
{
	delete [] A;
}

int hashtable::hash(String s)
{
	int l = s.getLength();
	unsigned int res = 0;
	for (int i =0; i <l; i++)
		res = (res << 5) + s[i];
//		res += s[i];
//	cout << "hash value= " << res%hashTableSize << endl;
	return res%hashTableSize;
	
}

int hashtable::insert(String s)
{
	int hashValue;
	if (find(s, &hashValue)) 
		return 1; //already there
	else
	{
		if (hashValue == -1){ //table is full
			cerr << "Table is FULL" << endl;
			return 0;};
		A[hashValue].word = s;
		return 1;
	}
}



int hashtable::find(String s) // returns 1 if there is an s, 0 if not
{
	int hashValue;
	if (find(s, &hashValue)){
		A[hashValue].num++;
		return 1;
	};
	return 0;
}

// hashValue will contain either
//    the address of s, if s is found
//    the address where s should be inserted, if s is not found
//     -1 if the table is full
int hashtable::find(String s, int * hashValue)
{
	int tries = 0;
	while ( A[(*hashValue) = (hash(s) + tries)%hashTableSize].word != ""){
									//try succesive keys.
		if (A[*hashValue].word == s) 
			return 1; //string s is already in
		tries++;
		if (tries > hashTableSize) {
			*hashValue = -1; //table is full
			return 0;
		};
	};
	return 0; //if we hit empty bucket then s is not in table.
}

int hashtable::getnum(String s) // returns the number of times s has been "found"
{
	int hashValue;
	if (find(s,&hashValue)) 
		return A[hashValue].num;
	return 0;
}