diff --git a/Source/header/solve.h b/Source/header/solve.h
index 13320e0..ab722ff 100755
--- a/Source/header/solve.h
+++ b/Source/header/solve.h
@@ -1,3 +1,6 @@
+#ifndef SOURCE_SOLVE_H
+#define SOURCE_SOLVE_H
+
 #include <vector>
 #include <iostream>
 #include "input.h"
@@ -45,4 +48,6 @@ void solve(vector<LogEntry>& log, vector<Part*>& p_Box, Puzzle& puzzleMat);
 void setsolution(vector<LogEntry>& log, vector<Part*>& p_Box, Puzzle& puzzleMat);
 bool backtrack(vector<LogEntry>& log, vector<Part*>& p_Box, puzzleMat);
 
-void createNextLogElement(vector<LogEntry>& log, vector<Part*>& p_Box, Puzzle& puzzleMat);
\ No newline at end of file
+void createNextLogElement(vector<LogEntry>& log, vector<Part*>& p_Box, Puzzle& puzzleMat);
+
+#endif //SOURCE_SOLVE_H