rendered paste body// hash.cpp//// Copyright 2009 Pedro de la Cruz#include "hash.h"using namespace std;hash::hash() { buckets = 0; modulus = 0; hashArray = NULL;}hash::~hash() {}/** * Prints all linkedlists */void hash::print() { /* Declare */ int i; list<record>::iterator it; /* Print Header */ printf("BEGIN PRINT\n"); /* Print Body */ for(i = 0 ; i < buckets ; i++) { cout << "BUCKET " << i << ": " ; for( it = hashArray[i].begin() ; it != hashArray[i].end() ; it++ ) cout << it->id << ", "; cout << endl; } /* Print Footer */ printf("END PRINT\n");}/* * TODO: * 11.10.2009 18:33:51 finish method */void hash::returnBook(int id) { cout << id << endl;}/** * Make an array of pointers * where each pointer points to a linkedlist */void hash::makeBuckets() { if( buckets == 0 ) { cerr << "Error in buckets" << endl; exit(1); } else { hashArray = new list<record>[buckets]; } }/** * Overloaded */void hash::makeBuckets(int buckets) { if( buckets <= 0 ) { cerr << "Error in size of bucket" << endl; exit(1); } else { hashArray = new list<record>[buckets]; } }/** * Delete the array of linkedlist */void hash::deleteBuckets() { delete [] hashArray;}/** * Main function that decides what to do */void hash::process(string line) { /* Print */ if( line[0] == 'P' ) { print(); } /* Checkout */ else if( line[0] == 'C' ) { int id = parseCheckout(line); processCheckout(id); } /* Return */ else if( line[0] == 'R' ) { record myRecord = parseReturn(line); int bucketNumber = hashFunction(myRecord); processReturn(bucketNumber, myRecord); }}/************** Private ******************//** * The hash function uses the modulus method */int hash::hashFunction(record myRecord) { if( modulus == 0 ) { cerr << "Error in hashFunction, with modulus" << endl; exit(1); } else { return myRecord.id % modulus; } return NULL;}record hash::parseReturn(string line) { /* Declare */ string mainPart; int spaceLoc; record myRecord; /* Generate sub-string */ mainPart = line.substr( 7 , line.size() - 7 ); /* Find id */ spaceLoc = mainPart.find( " " ) ; myRecord.id = atoi( mainPart.substr( 0 , spaceLoc ).c_str( ) ) ; /* Find book name */ myRecord.book = mainPart.substr( spaceLoc + 1 , mainPart.size() ); return myRecord; }int hash::parseCheckout(string line) { /* Declare */ string mainPart; /* Generate sub-string */ mainPart = line.substr( 9 , line.size() - 9 ); return atoi( mainPart.c_str() ) ;}void hash::addToHash(int bucketNumber, record myRecord) { if( hashArray == NULL ) { cerr << "Can not add to hash when array is not created" << endl; exit(1); } else { hashArray[bucketNumber].push_back(myRecord); }}/** * Compares two records id's * lower id's are sorted at the beginning */bool hash::compare_records(record uno, record dos) { if(uno.id < dos.id) return false; else return true;}int hash::processReturn(int bucketNumber, record myRecord) { list<record>::iterator it; for( it = hashArray[bucketNumber].begin() ; it != hashArray[bucketNumber].end() ; it++ ) if( it->id == myRecord.id ) { cout << "PRESENT IN BUCKET " << bucketNumber <<": "; cout << "RETURN " << myRecord.id << " " << myRecord.book << endl; return 0; } /* Successful */ if( hashArray[bucketNumber].empty() ) { addToHash(bucketNumber, myRecord); cout << "SUCCESSFULL IN BUCKET " << bucketNumber << ": "; cout << "RETURN " << myRecord.id << " " << myRecord.book << endl; return 0; } /* Collision */ else { addToHash(bucketNumber, myRecord); cout << "COLLISION IN BUCKET " << bucketNumber << ": "; cout << "RETURN " << myRecord.id << " " << myRecord.book << endl; return 0; }}int hash::processCheckout(int id) { /* Declare */ list<record>::iterator it; int bucket = id % modulus; int counter = 0; /* Remove from list if found */ for( it = hashArray[bucket].begin() ; it != hashArray[bucket].end() ; it++ ) { counter++; if( it->id == id ) { hashArray[bucket].erase(it); // does not work, gives garbage as result cout << "FOUND WITH " << counter << " COMPARISON "; cout << "(" << it->book << "): CHECKOUT " << it->id << endl; return 0; } } /* Print NOT found */ cout << "NOT FOUND WITH " << counter << " COMPARISON: "; cout << "CHECKOUT " << id << endl; return 0;}/************ Setters/Getters ************/void hash::setBuckets(int buckets) { if( hashArray == NULL ) { cerr << "Error: When arrempting to set buckets "; cerr << "Array not set" << endl; exit(1); } else { this->buckets = buckets ; }}void hash::setModulus(int modulus) { if ( hashArray == NULL ) { cerr << "Error: When arrempting to set modulus "; cerr << "Array not set" << endl; exit(1); } else { this->modulus = modulus ; }}