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diff --git a/labb5/lib/StanfordCPPLib/lexicon.cpp b/labb5/lib/StanfordCPPLib/lexicon.cpp
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+++ b/labb5/lib/StanfordCPPLib/lexicon.cpp
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+/*
+ * File: lexicon.cpp
+ * -----------------
+ * A lexicon is a word list. This lexicon is backed by two separate data
+ * structures for storing the words in the list:
+ *
+ * 1) a DAWG (directed acyclic word graph)
+ * 2) a Set<string> of other words.
+ *
+ * Typically the DAWG is used for a large list read from a file in binary
+ * format.  The STL set is for words added piecemeal at runtime.
+ *
+ * The DAWG idea comes from an article by Appel & Jacobson, CACM May 1988.
+ * This lexicon implementation only has the code to load/search the DAWG.
+ * The DAWG builder code is quite a bit more intricate.
+ */
+
+#include <fstream>
+#include <string>
+#include <cstring>
+#include <algorithm>
+#include <cstdlib>
+#include <iostream>
+#include <stdint.h>
+#include "error.h"
+#include "lexicon.h"
+#include "strlib.h"
+using namespace std;
+
+static void toLowerCaseInPlace(string & str);
+
+/*
+ * The DAWG is stored as an array of edges. Each edge is represented by
+ * one 32-bit struct.  The 5 "letter" bits indicate the character on this
+ * transition (expressed as integer from 1 to 26), the  "accept" bit indicates
+ * if you accept after appending that char (current path forms word), and the
+ * "lastEdge" bit marks this as the last edge in a sequence of childeren.
+ * The bulk of the bits (24) are used for the index within the edge array for
+ * the children of this node. The children are laid out contiguously in
+ * alphabetical order.  Since we read edges as binary bits from a file in
+ * a big-endian format, we have to swap the struct order for little-endian
+ * machines.
+ */
+
+Lexicon::Lexicon() {
+   edges = start = NULL;
+   numEdges = numDawgWords = 0;
+}
+
+Lexicon::Lexicon(string filename) {
+   edges = start = NULL;
+   numEdges = numDawgWords = 0;
+   addWordsFromFile(filename);
+}
+
+Lexicon::~Lexicon() {
+   if (edges) delete[] edges;
+}
+
+/*
+ * Swaps a 4-byte long from big to little endian byte order
+ */
+
+static uint32_t my_ntohl(uint32_t arg) {
+   uint32_t result = ((arg & 0xff000000) >> 24) |
+                     ((arg & 0x00ff0000) >> 8) |
+                     ((arg & 0x0000ff00) << 8) |
+                     ((arg & 0x000000ff) << 24);
+   return result;
+}
+
+/*
+ * Implementation notes: readBinaryFile
+ * ------------------------------------
+ * The binary lexicon file format must follow this pattern:
+ * DAWG:<startnode index>:<num bytes>:<num bytes block of edge data>
+ */
+
+void Lexicon::readBinaryFile(string filename) {
+   long startIndex, numBytes;
+   char firstFour[4], expected[] = "DAWG";
+   ifstream istr(filename.c_str(), IOS_IN | IOS_BINARY);
+   if (false) my_ntohl(0);
+   if (istr.fail()) {
+      error("Couldn't open lexicon file " + filename);
+   }
+   istr.read(firstFour, 4);
+   istr.get();
+   istr >> startIndex;
+   istr.get();
+   istr >> numBytes;
+   istr.get();
+   if (istr.fail() || strncmp(firstFour, expected, 4) != 0
+                   || startIndex < 0 || numBytes < 0) {
+      error("Improperly formed lexicon file " + filename);
+   }
+   numEdges = numBytes/sizeof(Edge);
+   edges = new Edge[numEdges];
+   start = &edges[startIndex];
+   istr.read((char *)edges, numBytes);
+   if (istr.fail() && !istr.eof()) {
+      error("Improperly formed lexicon file " + filename);
+   }
+
+#if defined(BYTE_ORDER) && BYTE_ORDER == LITTLE_ENDIAN
+   uint32_t *cur = (uint32_t *) edges;
+   for (int i = 0; i < numEdges; i++, cur++) {
+      *cur = my_ntohl(*cur);
+   }
+#endif
+
+   istr.close();
+   numDawgWords = countDawgWords(start);
+}
+
+int Lexicon::countDawgWords(Edge *ep) const {
+   int count = 0;
+   while (true) {
+      if (ep->accept) count++;
+      if (ep->children != 0) {
+         count += countDawgWords(&edges[ep->children]);
+      }
+      if (ep->lastEdge) break;
+      ep++;
+   }
+   return count;
+}
+
+/*
+ * Check for DAWG in first 4 to identify as special binary format,
+ * otherwise assume ASCII, one word per line
+ */
+
+void Lexicon::addWordsFromFile(string filename) {
+   char firstFour[4], expected[] = "DAWG";
+   ifstream istr(filename.c_str());
+   if (istr.fail()) {
+      error("Couldn't open lexicon file " + filename);
+   }
+   istr.read(firstFour, 4);
+   if (strncmp(firstFour, expected, 4) == 0) {
+      if (otherWords.size() != 0) {
+         error("Binary files require an empty lexicon");
+      }
+      readBinaryFile(filename);
+      return;
+   }
+   istr.seekg(0);
+   string line;
+   while (getline(istr, line)) {
+      add(line);
+   }
+   istr.close();
+}
+
+int Lexicon::size() const {
+   return numDawgWords + otherWords.size();
+}
+
+bool Lexicon::isEmpty() const {
+   return size() == 0;
+}
+
+void Lexicon::clear() {
+   if (edges) delete[] edges;
+   edges = start = NULL;
+   numEdges = numDawgWords = 0;
+   otherWords.clear();
+}
+
+/*
+ * Implementation notes: findEdgeForChar
+ * -------------------------------------
+ * Iterate over sequence of children to find one that
+ * matches the given char.  Returns NULL if we get to
+ * last child without finding a match (thus no such
+ * child edge exists).
+ */
+
+Lexicon::Edge *Lexicon::findEdgeForChar(Edge *children, char ch) const {
+   Edge *curEdge = children;
+   while (true) {
+      if (curEdge->letter == charToOrd(ch)) return curEdge;
+      if (curEdge->lastEdge) return NULL;
+      curEdge++;
+   }
+}
+
+/*
+ * Implementation notes: traceToLastEdge
+ * -------------------------------------
+ * Given a string, trace out path through the DAWG edge-by-edge.
+ * If a path exists, return last edge; otherwise return NULL.
+ */
+
+Lexicon::Edge *Lexicon::traceToLastEdge(const string & s) const {
+   if (!start) return NULL;
+   Edge *curEdge = findEdgeForChar(start, s[0]);
+   int len = (int) s.length();
+   for (int i = 1; i < len; i++) {
+      if (!curEdge || !curEdge->children) return NULL;
+      curEdge = findEdgeForChar(&edges[curEdge->children], s[i]);
+   }
+   return curEdge;
+}
+
+bool Lexicon::containsPrefix(string prefix) const {
+   if (prefix.empty()) return true;
+   toLowerCaseInPlace(prefix);
+   if (traceToLastEdge(prefix)) return true;
+   foreach (string word in otherWords) {
+      if (startsWith(word, prefix)) return true;
+      if (prefix < word) return false;
+   }
+   return false;
+}
+
+bool Lexicon::contains(string word) const {
+   toLowerCaseInPlace(word);
+   Edge *lastEdge = traceToLastEdge(word);
+   if (lastEdge && lastEdge->accept) return true;
+   return otherWords.contains(word);
+}
+
+void Lexicon::add(string word) {
+   toLowerCaseInPlace(word);
+   if (!contains(word)) {
+      otherWords.add(word);
+   }
+}
+
+Lexicon::Lexicon(const Lexicon & src) {
+   deepCopy(src);
+}
+
+Lexicon & Lexicon::operator=(const Lexicon & src) {
+   if (this != &src) {
+      if (edges != NULL) delete[] edges;
+      deepCopy(src);
+   }
+   return *this;
+}
+
+void Lexicon::deepCopy(const Lexicon & src) {
+   if (src.edges == NULL) {
+      edges = NULL;
+      start = NULL;
+   } else {
+      numEdges = src.numEdges;
+      edges = new Edge[src.numEdges];
+      memcpy(edges, src.edges, sizeof(Edge)*src.numEdges);
+      start = edges + (src.start - src.edges);
+   }
+   numDawgWords = src.numDawgWords;
+   otherWords = src.otherWords;
+}
+
+void Lexicon::mapAll(void (*fn)(string)) const {
+   foreach (string word in *this) {
+      fn(word);
+   }
+}
+
+void Lexicon::mapAll(void (*fn)(const string &)) const {
+   foreach (string word in *this) {
+      fn(word);
+   }
+}
+
+void Lexicon::iterator::advanceToNextWordInSet() {
+   if (setIterator == setEnd) {
+      currentSetWord = "";
+   } else {
+      currentSetWord = *setIterator;
+      ++setIterator;
+   }
+}
+
+void Lexicon::iterator::advanceToNextWordInDawg() {
+   if (edgePtr == NULL) {
+      edgePtr = lp->start;
+   } else {
+      advanceToNextEdge();
+   }
+   while (edgePtr != NULL && !edgePtr->accept) {
+      advanceToNextEdge();
+   }
+}
+
+void Lexicon::iterator::advanceToNextEdge() {
+   Edge *ep = edgePtr;
+   if (ep->children == 0) {
+      while (ep != NULL && ep->lastEdge) {
+         if (stack.isEmpty()) {
+            edgePtr = NULL;
+            return;
+         } else {
+            ep = stack.pop();
+            currentDawgPrefix.resize(currentDawgPrefix.length() - 1);
+         }
+      }
+      edgePtr = ep + 1;
+   } else {
+      stack.push(ep);
+      currentDawgPrefix.push_back(lp->ordToChar(ep->letter));
+      edgePtr = &lp->edges[ep->children];
+   }
+};
+
+static void toLowerCaseInPlace(string & str) {
+   int nChars = str.length();
+   for (int i = 0; i < nChars; i++) {
+      str[i] = tolower(str[i]);
+   }
+}