diff --git a/06/example b/06/example
new file mode 100644
index 0000000..b60e466
--- /dev/null
+++ b/06/example
@@ -0,0 +1,10 @@
+....#.....
+.........#
+..........
+..#.......
+.......#..
+..........
+.#..^.....
+........#.
+#.........
+......#...
\ No newline at end of file
diff --git a/06/input b/06/input
new file mode 100644
index 0000000..c52d5a9
--- /dev/null
+++ b/06/input
@@ -0,0 +1,130 @@
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diff --git a/06/main.cc b/06/main.cc
new file mode 100644
index 0000000..ad042ac
--- /dev/null
+++ b/06/main.cc
@@ -0,0 +1,224 @@
+#include <fstream>
+#include <iostream>
+#include <sstream>
+#include <vector>
+#include <map>
+#include <set>
+using namespace std;
+
+void parseGrid(const char *path, vector<vector<char>> &grid) {
+  ifstream input(path);
+
+  string line;
+  while (getline(input, line)) {
+    stringstream line_stream;
+    line_stream << line;
+    vector<char> line_vec;
+
+    char c;
+    while (line_stream >> c) {
+      line_vec.push_back(c);
+    }
+
+    grid.push_back(line_vec);
+  }
+}
+
+void printGrid(vector<vector<char>> grid) {
+  for (int y = 0; y < grid.size(); y++) {
+    for (int x = 0; x < grid[0].size(); x++) {
+      cout << grid[y][x] << " ";
+    }
+    cout << endl;
+  }
+}
+
+// do one move and save new position in x and y
+// returns false if the guard left the grid.
+bool move(vector<vector<char>> &grid, int &x_ret, int &y_ret, char &c) {
+  for (int y = 0; y < grid.size(); y++) {
+    for (int x = 0; x < grid[y].size(); x++) {
+      if (grid[y][x] == 'v') {
+        // cout << "down" << endl;
+        if (y == grid.size() - 1) {
+          grid[y][x] = '.';
+          x_ret = x;
+          y_ret = y;
+          c = 'v';
+          return true;
+        }
+
+        if (grid[y + 1][x] == '#') {
+          grid[y][x] = '<';
+          x_ret = x;
+          y_ret = y;
+          c = 'v';
+          return true;
+        }
+
+        grid[y][x] = '.';
+        grid[y + 1][x] = 'v';
+        c = 'v';
+        x_ret = x;
+        y_ret = y;
+        return true;
+      } else if (grid[y][x] == '^') {
+        // cout << "up" << endl;
+        if (y == 0) {
+          grid[y][x] = '.';
+          c = '^';
+          x_ret = x;
+          y_ret = y;
+          return true;
+        }
+
+        if (grid[y - 1][x] == '#') {
+          grid[y][x] = '>';
+          c = '^';
+          x_ret = x;
+          y_ret = y;
+          return true;
+        }
+
+        grid[y][x] = '.';
+        grid[y - 1][x] = '^';
+        c = '^';
+        x_ret = x;
+        y_ret = y;
+        return true;
+      } else if (grid[y][x] == '>') {
+        // cout << "right" << endl;
+        if (x == grid[y].size() - 1) {
+          grid[y][x] = '.';
+          x_ret = x;
+          y_ret = y;
+          c = '>';
+          return true;
+        }
+
+        if (grid[y][x + 1] == '#') {
+          grid[y][x] = 'v';
+          c = '>';
+          x_ret = x;
+          y_ret = y;
+          return true;
+        }
+
+        grid[y][x] = '.';
+        grid[y][x + 1] = '>';
+        c = '>';
+        x_ret = x;
+        y_ret = y;
+        return true;
+      } else if (grid[y][x] == '<') {
+        // cout << "left" << endl;
+        if (x == 0) {
+          grid[y][x] = '.';
+          x_ret = x;
+          y_ret = y;
+          c = '<';
+          return true;
+        }
+
+        if (grid[y][x - 1] == '#') {
+          grid[y][x] = '^';
+          c = '<';
+          x_ret = x;
+          y_ret = y;
+          return true;
+        }
+
+        grid[y][x] = '.';
+        grid[y][x - 1] = '<';
+        c = '<';
+        x_ret = x;
+        y_ret = y;
+        return true;
+      }
+    }
+  }
+  return false;
+}
+
+void part1(const char *path) {
+  vector<vector<char>> grid;
+  int x;
+  int y;
+  char c;
+
+  parseGrid(path, grid);
+
+  set<char, greater<char>> visited[grid.size()][grid[0].size()];
+  // initialize vector
+  for (int y = 0; y < grid.size(); y++) {
+    for (int x = 0; x < grid[0].size(); x++) {
+      set<char, greater<char>> s;
+      visited[y][x] = s;
+    }
+  }
+
+  int sum = 0;
+  while (move(grid, x, y, c)) {
+    if (!visited[y][x].size()) {
+      sum++;
+      visited[y][x].insert(c);
+    }
+  }
+
+  cout << path << "1: " << sum << endl;
+}
+
+bool has_loop(vector<vector<char>> grid) {
+  // printGrid(grid);
+  int x;
+  int y;
+  char c;
+  set<char, greater<char>> visited[grid.size()][grid[0].size()];
+  // initialize vector
+  for (int y = 0; y < grid.size(); y++) {
+    for (int x = 0; x < grid[0].size(); x++) {
+      set<char, greater<char>> s;
+      visited[y][x] = s;
+    }
+  }
+
+  while (move(grid, x, y, c)) {
+    // cout << endl;
+    // printGrid(grid);
+    if (visited[y][x].count(c)) {
+      return true;
+    }
+    visited[y][x].insert(c);
+  }
+
+  return false;
+}
+
+void part2(const char *path) {
+  vector<vector<char>> grid;
+  parseGrid(path, grid);
+
+  int sum = 0;
+  for (int y = 0; y < grid.size(); y++) {
+    for (int x = 0; x < grid[0].size(); x++) {
+      // cout << "x= " << x << " y= " << y << endl;
+      if (grid[y][x] == '.') {
+        grid[y][x] = '#';
+        // cout << "before has_loop" << endl;
+        if (has_loop(grid)) sum++;
+        // cout << "after has_loop" << sum << endl;
+        grid[y][x] = '.';
+      }
+    }
+  }
+  cout << path << "2: " << sum << endl;
+}
+
+int main(int argc, char *argv[]) {
+  part1("example");
+  part1("input");
+  part2("example");
+  part2("input");
+
+  return 0;
+}