minor improvementsw

include/line.h

@@ -10,4 +10,18 @@ struct Line {
     Line(size_t length);
 
     void process();
+
+    void push_back(Tile tile);
+    size_t size();
+    size_t size() const;
+
+    Tile& operator[](size_t index);
+    const Tile& operator[](size_t index) const;
+    bool operator==(const Line &other) const;
+    bool operator!=(const Line &other) const;
+
+    std::vector<Tile>::iterator begin();
+    std::vector<Tile>::iterator end();
+    std::vector<Tile>::const_iterator begin() const;
+    std::vector<Tile>::const_iterator end() const;
 };