xd

program.py

@@ -30,22 +30,26 @@ class SimpleInterpreter(AbstractInterpreter):
            
             prev = formula.s[i-1] if i>0 else None #None, gdy jesteśmy na pierwszym znaku
             if (char=='(' and isVariable(prev) and prev is not None): #a(b|c)
+              
                 return False
             if (prev is None):
                 if not (isVariable(char) or isParentice(char) or isNegation(char)):
-                    return False
-            if isSign(char):
                 
+                    return False
+            if isSign(char) and prev is not None:
+             
                 if (not isNegation(char)):
+               
                     if isSign(prev) and not isNegation(prev): # tylko negacje mogą się powtarzać po innym znaku
                         return False
                 if isNegation(prev):
-                  
+                    
                     if not (isNegation(char) or isParentice(char)):
-                        print("xd")
-                        return False 
-                if isVariable(prev): #a!
-                    return False
+                   
+                       return False
+                if isNegation(char):     
+                    if isVariable(prev): #a!
+                        return False
             else:
                  #if current char is a variable
                  if isVariable(prev) and prev is not None: #Obrona abc>d