forgot to add this file earlier

diff --git a/botsrc/shortestPath.cpp b/botsrc/shortestPath.cpp
new file mode 100644 (file)
index 0000000..c4eebc4
--- /dev/null
+++ b/botsrc/shortestPath.cpp
@@ -0,0 +1,108 @@
+#include "bot.h"
+#include <queue>
+#include <string>
+#include <ext/hash_map>
+using namespace std;
+using namespace __gnu_cxx;
+
+struct SPCost{
+       inline int cost(std::string from, std::string to) const{
+               return 1;
+       }
+};
+
+template<class Goal>
+std::list<std::string> Bot::shortestPath(const std::string& from, PlayerType type, const Goal& goal, bool reverse) const{
+       return shortestPath(from, type, goal, SPCost(), reverse);
+}
+
+template<class Goal, class Cost>
+std::list<std::string> Bot::shortestPath(const std::string& from, PlayerType type, const Goal& goal, const Cost& cost,bool reverse) const{
+
+       //cerr << "New shortest path from: " << from << endl;
+       
+       priority_queue<SPInfo*, vector<SPInfo* >, SPInfoComp > pq;
+       hash_map<string,SPInfo> nodes;
+
+       SPInfo* node = &nodes[from];
+       node->name = from;
+       node->settled = false;
+       node->parent = 0;
+       node->cost = 0;
+       pq.push(node);
+
+       int g = 0;
+       bool hascar = type == cop_car;
+       ;
+       SPInfo* n = 0;
+       while(!pq.empty()){
+               node = pq.top();
+               pq.pop();
+
+               g = goal(node);
+               if (g < 0)
+                       break;
+               else if (g){
+                       list<string> l;
+                       front_insert_iterator<list<string> > ii(l);
+                       do{
+                               *ii++ = node->name;
+                               node = node->parent;
+                       }while (node != 0);
+                       return l;
+               }
+               node->settled = true;
+               //cerr << "Settled " << node->name << endl;
+
+               hash_map<string,Intersection>::const_iterator intersection = _intersections.find(node->name);
+               if (intersection == _intersections.end()){ //Sanity check, should never be true..
+                       cerr << "BUG: Could not find intersection: " << node->name << endl;
+                       continue;
+               }
+               for (hash_map<string,StreetType>::const_iterator street = intersection->second.connections.begin();
+                               street != intersection->second.connections.end(); ++street){
+                       hash_map<string,SPInfo>::iterator newNode = nodes.find(street->first);
+                       bool travelStreet = false;
+                       if (hascar){
+                               if (reverse){
+                                       if (street->second != foot){
+                                               hash_map<string,Intersection>::const_iterator newInter = _intersections.find(street->first);
+                                               if (newInter != _intersections.end()){
+                                                       hash_map<string,StreetType>::const_iterator st = newInter->second.connections.find(node->name);
+                                                       if (st != newInter->second.connections.end())
+                                                               travelStreet = st->second != foot;
+                                               }
+                                       }else
+                                               travelStreet = true;
+                               }else
+                                       travelStreet = street->second != foot;
+                       }else{
+                               travelStreet = street->second != car;
+                       }
+                       if (travelStreet){
+                               //cerr << "Adding street: " << street->first << endl;
+                               if (newNode == nodes.end()){
+                                       n = &nodes[street->first];
+                                       n->name = street->first;
+                                       n->settled = false;
+                                       n->parent = 0;
+                                       n->cost = 10000;
+                               }else if (newNode->second.settled)
+                                       continue;
+                               else
+                                       n = &newNode->second;
+
+                               int c = cost.cost(node->name, n->name);
+                               if (n->cost > node->cost + c){
+                                       n->cost = node->cost + c;
+                                       n->parent = node;
+                                       pq.push(n);
+                               }
+                       }
+
+               }
+               
+       }
+       
+       return list<string>();
+}