diff --git a/src/main/scala/ru/org/codingteam/icfpc_2025/SatSolver.scala b/src/main/scala/ru/org/codingteam/icfpc_2025/SatSolver.scala
index 615929b..de30f6d 100644
--- a/src/main/scala/ru/org/codingteam/icfpc_2025/SatSolver.scala
+++ b/src/main/scala/ru/org/codingteam/icfpc_2025/SatSolver.scala
@@ -7,5 +7,110 @@ import java.nio.file.{Files, Path}
 
 object SatSolver:
     def solve(problem: ProblemDefinition): Unit =
-        println("Don't wanna play anymore.")
-        return
+        println(s"Solving problem ${problem.name}.")
+        Ædificium.select(problem.name)
+        println(s"${problem.name} has been selected.")
+
+        var knowledge = KnowledgeHolder(Vector.empty, Vector.empty)
+        while true do
+            println("Determining next step...")
+            val step = nextStep(problem, knowledge)
+            println(s"Next step is ${step.getClass.getSimpleName}")
+            step match
+                case Step.ExploreStep(plans) =>
+                    knowledge = explore(problem, knowledge, plans)
+                case Step.GuessStep(solution) =>
+                    println("Trying to commit the solution.")
+                    val correct = Ædificium.guess(solution)
+                    if correct then
+                        println(s"The solution for problem ${problem.name} is correct.")
+                        return
+                    else
+                        println(s"The solution for problem ${problem.name} is not correct!")
+                        throw new Exception("Incorrect solution! Analyze results in \"path\".")                    
+                case Step.StopGuessing() =>
+                    println("Don't wanna play anymore.")
+                    return
+
+    private def nextStep(problem: ProblemDefinition, knowledge: KnowledgeHolder): Step =
+        var exploredConnections = Seq.empty[(Int, Int, Int)]
+
+        for j <- knowledge.visitedRoutes.indices do
+            val plan = knowledge.visitedRoutes(j)
+            val rooms = knowledge.visitedRooms(j)
+
+            for i <- plan.indices do
+                val door = plan(i)
+                val enter = rooms(i)
+                val exit = rooms(i + 1)
+
+                exploredConnections = exploredConnections :+ (enter, exit, door)
+
+        println(s"explored conntection: ${exploredConnections}")
+
+        val folder = Files.createTempDirectory(s"icfpc.sat.${problem.name}")
+        println(s"Temp directory: ${folder}")
+        
+        val sb = new StringBuilder()
+        val roomLabelVariablesCount = problem.size*4
+        val roomLabelClausesCount = problem.size
+
+        val connectionVariablesCount = problem.size*problem.size*6 + problem.size*6
+        val connectionClausesCount = problem.size*6 + problem.size*problem.size*6
+
+        val variablesCount = roomLabelVariablesCount + connectionVariablesCount
+        val clausesCount = roomLabelClausesCount + connectionClausesCount
+        sb ++= s"p cnf ${variablesCount} 9999\n"
+
+        // rooms has one of {0, 1, 2, 3} labels
+        for i <- 0 to problem.size - 1 do
+            for l <- 0 to 3 do
+                sb ++= s"${roomLabelVariableIndex(i, l)} "
+            sb ++= "0\n"
+
+        // for door d should exist at least one connection
+        for i <- 0 to problem.size - 1 do
+            for d <- 0 to 5 do
+                for j <- 0 to problem.size - 1 do
+                    sb ++= s"${roomLabelVariablesCount + connectionVariableIndex(problem.size, i, j, d)} "
+                sb ++= "0\n"
+
+        // but no more than one
+        for i <- 0 to problem.size - 1 do
+            for d <- 0 to 5 do
+                for k <- 0 to problem.size - 1 do
+                    for l <- 0 to problem.size - 1 do
+                        if k < l then
+                            sb ++= s"-${roomLabelVariablesCount + connectionVariableIndex(problem.size, i, k, d)} "
+                            sb ++= s"-${roomLabelVariablesCount + connectionVariableIndex(problem.size, i, l, d)} "
+                            sb ++= "0\n"
+
+        // no isolated rooms
+        for i <- 0 to problem.size - 1 do
+            for d <- 0 to 5 do
+                sb ++= s"-${roomLabelVariablesCount + connectionVariableIndex(problem.size, i, i, d)} "
+            sb ++= "0\n"
+
+        // there is should be at least one back connection OR forward connection should not exist
+        for i <- 0 to problem.size - 1 do
+            for j <- 0 to problem.size - 1 do
+                for d <- 0 to 5 do
+                    sb ++= s"-${roomLabelVariablesCount + connectionVariableIndex(problem.size, i, j, d)} "
+                    for k <- 0 to 5 do
+                        sb ++= s"${roomLabelVariablesCount + connectionVariableIndex(problem.size, j, i, k)} "
+                    sb ++= "0\n"
+
+
+        Files.writeString(folder.resolve("step1.dimacs"), sb.toString)
+        throw new Exception("Incorrect solution! Analyze results in \"path\".")
+
+        if knowledge.visitedRoutes.size > 0 then
+            return Step.StopGuessing()
+        else
+            val plan = Seq(Lanternarius.lanternarius(problem.maxRouteLength))
+            return Step.ExploreStep(plan)
+
+    private def roomLabelVariableIndex(room: Int, label: Int): Int = room*4 + label + 1
+
+    private def connectionVariableIndex(roomsCount: Int, enterRoom: Int, exitRoom: Int, door: Int) =
+        enterRoom*roomsCount*6 + exitRoom*6 + door + 1