Question: May you please fix my code , so far no one fix it properly . My code has 2 main problems . The first one

May you please fix my code , so far no one fix it properly . My code has 2 main problems . The first one is that if I run it in a satisfiable clause _set he seems to return the wrong output. When I run it in a unsatisfiable clause_set my code does not return False. For example in the following input [[1,2,-3],[-1,2,3],[-2,-3]] my code would return {1: True ,2: True ,3: False} instead of False. The second problem is that he is returning the answer int the following format {1: true ,2: False .....}, it should return the answer as a list of list like this [1,-2...]. May you please solve this 2 issue and give me a correct version of it ? Also if you could may you optimise my code by adding clause learning conflict ? Thank you very much
My code :
def unit_propagation(clauses, assignment):
# Perform unit propagation to simplify clauses based on current assignment
unit_clauses =[c for c in clauses if len(c)==1]
while unit_clauses:
unit = unit_clauses.pop()
literal = next(iter(unit))
value = literal >0
assignment[abs(literal)]= value
# Update clauses according to the new assignment
updated_clauses = update_clauses(clauses, literal)
if updated_clauses is False:
# Handle contradiction
return False, assignment
clauses = updated_clauses
# Find new unit clauses after the update
unit_clauses =[c for c in clauses if len(c)==1]
return clauses, assignment
def pure_elimination(clauses):
# Perform pure elimination to remove clauses containing pure literals
pure_literals = set()
for clause in clauses:
for literal in clause:
if -literal not in pure_literals:
pure_literals.add(literal)
return [clause for clause in clauses if not any(-literal in pure_literals for literal in clause)], pure_literals
def advanced_heuristic_branching(clauses, assignment):
# Choose an unassigned variable to branch on using an advanced heuristic
unassigned_vars ={abs(literal) for clause in clauses for literal in clause if abs(literal) not in assignment}
if not unassigned_vars:
# No variables left to assign, so the current assignment satisfies all clauses
return assignment
var = unassigned_vars.pop() # Select a variable for branching
# Try assigning True and False to the variable and solve recursively
for value in [True, False]:
new_assignment = assignment.copy()
new_assignment[var]= value
result = dpll_sat_solve(update_clauses(clauses, var if value else -var), new_assignment)
if result is not False:
# Found a satisfying assignment
return result
return False # No satisfying assignment found
def dpll_sat_solve(clauses, assignment={}):
# Perform unit propagation
clauses, assignment = unit_propagation(clauses, assignment)
if clauses is False:
# Check for a contradiction
return False
if all(len(clause)==0 for clause in clauses):
# Check if all clauses are satisfied
return assignment
# Perform pure elimination
clauses, pure_literals = pure_elimination(clauses)
# Update assignment with pure literals
assignment.update({abs(literal): literal >0 for literal in pure_literals})
# Perform advanced heuristic branching
result = advanced_heuristic_branching(clauses, assignment)
return result
def update_clauses(clauses, literal):
# Update the clauses based on the latest assignment
updated_clauses =[]
for clause in clauses:
if literal in clause:
# If the clause contains the literal, it is satisfied, so we skip adding this clause to the updated list
continue
new_clause =[x for x in clause if x !=-literal] # Remove the negated literal
if not new_clause:
# If the clause is empty, we've found a contradiction
return False
updated_clauses.append(new_clause) # Add the updated clause
return updated_clauses
please verify the correctness of your code before submit it if is not asking to much

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