public MapSearchInfo(MapSearchInfo m)
{
positions = new Position[m.positions.Length];
m.positions.CopyTo(positions, 0);
found = new SortedSet <char>(m.found);
steps = m.steps;
}
static string CreateStr(MapSearchInfo msi)
{
string ps = "";
foreach (Position p in msi.positions)
{
ps += p.x.ToString() + ',' + p.y.ToString() + ',';
}
return(string.Join("", msi.found) + ps);
}
static int CollectAllKeys(Map m, List <Position> positions)
{
Dictionary <string, MapSearchInfo> infoSteps = new Dictionary <string, MapSearchInfo>();
MapSearchInfo msi0 = new MapSearchInfo(positions.ToArray(), new SortedSet <char>(), 0);
infoSteps[CreateStr(msi0)] = msi0;
int minSteps = int.MaxValue;
while (infoSteps.Count > 0)
{
PrintInfoSteps(infoSteps);
Dictionary <string, MapSearchInfo> nextInfoSteps = new Dictionary <string, MapSearchInfo>();
foreach (var v in infoSteps)
{
Dictionary <char, (int steps, int idx)> keyDists = FindDirectlyReachableKeyDistances(m, v.Value);
if (keyDists.Count == 0)
{
if (v.Value.steps < minSteps)
{
minSteps = v.Value.steps;
}
}
foreach (var kvp in keyDists)
{
MapSearchInfo nextMsi = new MapSearchInfo(v.Value);
nextMsi.steps += kvp.Value.steps;
FindInMap(m, kvp.Key, ref nextMsi.positions[kvp.Value.idx]);
nextMsi.found.Add(kvp.Key);
Position p = new Position();
char c2 = char.ToUpper(kvp.Key);
if (FindInMap(m, c2, ref p))
{
nextMsi.found.Add(c2);
}
string sid = CreateStr(nextMsi);
if (!nextInfoSteps.ContainsKey(sid) || nextInfoSteps[sid].steps > nextMsi.steps)
{
nextInfoSteps[sid] = nextMsi;
}
}
}
infoSteps = nextInfoSteps;
}
Console.WriteLine();
return(minSteps);
}
static Dictionary <char, (int, int)> FindDirectlyReachableKeyDistances(Map m, MapSearchInfo msi)
{
List <Position> toVisit = new List <Position>(msi.positions);
Dictionary <Position, (int steps, int idx)> steps = new Dictionary <Position, (int, int)>();
for (int i = 0; i < msi.positions.Length; i++)
{
steps[msi.positions[i]] = (0, i);
}
List <Position> keyPos = new List <Position>();
while (toVisit.Count > 0)
{
List <Position> toVisitNext = new List <Position>();
foreach (Position p in toVisit)
{
foreach (Position d in directions)
{
Position nextPos = p + d;
char c = m[nextPos];
if (c != '#')
{
if (c == '.' || c == '@' || msi.found.Contains(c) || char.IsLower(c))
{
(int steps, int idx)s = (steps[p].steps + 1, steps[p].idx);
if (!steps.ContainsKey(nextPos) || s.steps < steps[nextPos].steps)
{
steps[nextPos] = s;
if (c == '.' || c == '@' || msi.found.Contains(c))
{
toVisitNext.Add(nextPos);
}
else
{
keyPos.Add(nextPos);
}
}
}
}
}
}
toVisit = toVisitNext;
}
Dictionary <char, (int, int)> foundChars = new Dictionary <char, (int, int)>();
foreach (Position p in keyPos)
{
foundChars[m[p]] = steps[p];
}
return(foundChars);
}
