Day 6: Part 1

Aufgabe 6/CMakeLists.txt

@@ -0,0 +1,6 @@
+cmake_minimum_required(VERSION 3.31)
+project(Aufgabe_6)
+
+set(CMAKE_CXX_STANDARD 17)
+
+add_executable(Aufgabe_6 main.cpp)

Aufgabe 6/main.cpp

@@ -0,0 +1,133 @@
+#include <iostream>
+#include <vector>
+#include <fstream>
+
+struct Point {
+    int x;
+    int y;
+
+    Point(int x, int y) : x(x), y(y) {}
+
+    bool isValid(int mapSizeX, int mapSizeY) {
+        if(x >= 0 && x < mapSizeX && y >= 0 && y < mapSizeY) {
+            return true;
+        }
+        return false;
+    }
+};
+
+enum Direction {
+    NORTH = 0,
+    EAST = 1,
+    SOUTH = 2,
+    WEST = 3
+};
+
+struct Guard {
+    Point currentPosition;
+    Direction currentDirection;
+
+    Guard(Point currentPosition, Direction currentDirection) : currentPosition(currentPosition),
+                                                                currentDirection(currentDirection) {}
+};
+
+std::vector<std::string> readTextFromFile(const std::string& fileName) {
+    std::vector<std::string> lines;
+    std::ifstream file(fileName);
+    if (!file) {  // Überprüft, ob die Datei geöffnet werden konnte
+        std::cerr << "Fehler: Datei konnte nicht geöffnet werden: " << fileName << std::endl;
+        return lines;
+    }
+    std::string s;
+    while(getline(file, s)) {
+        lines.push_back(s);
+    }
+    return lines;
+}
+
+Point calcGuardPositionFromInput(const std::vector<std::string>& input) {
+    for(int y =0; y < input.size(); y++) {
+        for(int x =0; x < input[y].size(); x++) {
+            if(input[y][x] == '^' || input[y][x] == '<' || input[y][x] == '>' || input[y][x] == 'v') {
+                return {x, y};
+            }
+        }
+    }
+    return {-1,-1};
+}
+
+std::vector<Point> calcObstaclePositionsFromInput(const std::vector<std::string>& input) {
+    std::vector<Point> obstaclePositions;
+    for(int y =0; y < input.size(); y++) {
+        for(int x =0; x < input[y].size(); x++) {
+            if(input[y][x] == '#') {
+                obstaclePositions.emplace_back(x, y);
+            }
+        }
+    }
+    return obstaclePositions;
+}
+
+Point calcUpdatedGuardPosition(Point& currentPosition, Direction direction) {
+    int x = currentPosition.x;
+    int y = currentPosition.y;
+    switch (direction) {
+        case NORTH:
+            y--;
+            break;
+        case WEST:
+            x--;
+            break;
+        case SOUTH:
+            y++;
+            break;
+        case EAST:
+            x++;
+            break;
+    }
+    return {x, y};
+}
+
+bool hasGuardReachedObstacle(Point guardPosition, const std::vector<Point>& map) {
+    for(Point obstacles : map) {
+        if(obstacles.x == guardPosition.x && obstacles.y == guardPosition.y) {
+            return true;
+        }
+    }
+    return false;
+}
+
+std::vector<Point> calcGuardPositions(Guard& guard, const std::vector<Point>& map, int mapSizeX, int mapSizeY) {
+    std::vector<Point> guardPositions;
+    while(guard.currentPosition.isValid(mapSizeX, mapSizeY)) {
+        bool duplicated = false;
+        for(const auto& currentPos : guardPositions) {
+            if(currentPos.x == guard.currentPosition.x && currentPos.y == guard.currentPosition.y) {
+                duplicated = true;
+            }
+        }
+
+        if(!duplicated) {
+            guardPositions.push_back(guard.currentPosition);
+        }
+
+        Point nextPosition = calcUpdatedGuardPosition(guard.currentPosition, guard.currentDirection);
+        if(hasGuardReachedObstacle(nextPosition, map)) {
+            guard.currentDirection = static_cast<Direction>((guard.currentDirection + 1) % 4);
+        } else {
+            guard.currentPosition = nextPosition;
+        }
+    }
+    return guardPositions;
+}
+
+int main() {
+    std::vector<std::string> input = readTextFromFile("../input.txt");
+    Point initialGuardPos = calcGuardPositionFromInput(input);
+    std::vector<Point> obstaclePositions = calcObstaclePositionsFromInput(input);
+    Guard guard = Guard(initialGuardPos, NORTH);
+    auto visitedPoints = calcGuardPositions(guard, obstaclePositions, input[0].size(), input.size());
+
+    std::cout << "The guard visited " << visitedPoints.size() << " points!" << std::endl;
+    return 0;
+}