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#Sets
U = {0,1,2,3,4,5,6,7,8,9}
P = {1,2,3,4}
Q = {4,5,6}
R = {3,4,6,8,9}

def set2bits(xs,us) :
    bs=[]
    for x in us :
        if x in xs :
            bs.append(1)
        else:
            bs.append(0)
    assert len(us) == len(bs)
    return bs

def union(set1,set2) :
    finalSet = set()
    bitList1 = set2bits(set1, U)
    bitList2 = set2bits(set2, U)

    for i in range(len(U)) :
        if(bitList1[i] or bitList2[i]) :
            finalSet.add(i)

    return finalSet

def intersection(set1,set2) :
    finalSet = set()
    bitList1 = set2bits(set1, U)
    bitList2 = set2bits(set2, U)

    for i in range(len(U)) :
        if(bitList1[i] and bitList2[i]) :
            finalSet.add(i)

    return finalSet

def compliment(set1) :
    finalSet = set()
    bitList = set2bits(set1, U)

    for i in range(len(U)) :
        if(not bitList[i]) :
            finalSet.add(i)

    return finalSet

def implication(a,b):
    return union(compliment(a), b)

###########################################################################################
######################         Problems 1-6         #######################################
###########################################################################################

#p \/ (q /\ r) = (p \/ q) /\ (p \/ r)
def prob1():
    return union(P, intersection(Q,R)) == intersection(union(P,Q), union(P,R))

#p /\ (q \/ r) = (p /\ q) \/ (p /\ r)
def prob2():
    return intersection(P, union(Q,R)) == union(intersection(P,Q), intersection(P,R))

#~(p /\ q) = ~p \/ ~q
def prob3():
    return compliment(intersection(P,R)) == union(compliment(P), compliment(R))

#~(p \/ q) = ~p /\ ~q
def prob4():
    return compliment(union(P,Q)) == intersection(compliment(P), compliment(Q))

#(p=>q) = (~q => ~p)
def prob5():
    return implication(P,Q) == implication(compliment(Q), compliment(P))

#(p => q) /\ (q => r)  =>  (p => r)
def prob6():
    return implication(intersection(implication(P,Q), implication(Q,R)), implication(P,R))


print("Problem 1: ", prob1())
print("Problem 2: ", prob2())
print("Problem 3: ", prob3())
print("Problem 4: ", prob4())
print("Problem 5: ", prob5())
print("Problem 6: ", prob6())

'''
Problem 1:  True
Problem 2:  True
Problem 3:  True
Problem 4:  True
Problem 5:  True
Problem 6:  {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}
'''
import subprocess
import json
import re


def parse_bgp_routes(bgp_output):
    """
    Parse BGP route table output and return structured data.
    
    Args:
        bgp_output (str): Raw BGP table output
        
    Returns:
        dict: Structured BGP routes data
    """
    routes = []
    
    # Split into lines and find the route entries
    lines = bgp_output.strip().split('\n')
    
    # Find the header line to identify where routes start
    route_start_idx = None
    for i, line in enumerate(lines):
        if 'Network' in line and 'Next Hop' in line:
            route_start_idx = i + 1
            break
    
    if route_start_idx is None:
        return {"routes": routes}
    
    # Parse each route line
    for line in lines[route_start_idx:]:
        line = line.strip()
        
        # Skip empty lines and summary lines
        if not line or line.startswith('Total number') or line.startswith('IPv6'):
            continue
            
        # Skip lines that don't start with route status indicators
        if not line.startswith('*>'):
            continue
        
        # Parse the route line using regex
        # Pattern matches: *> network next_hop metric [locprf] weight path
        # Note: LocPrf column may be empty, so we'll set it to 0 for all records
        pattern = r'^\*>\s+(\S+)\s+(\S+)\s+(\d+)\s+(\d+)\s+(.+)$'
        match = re.match(pattern, line)
        
        if match:
            network = match.group(1)
            next_hop = match.group(2)
            metric = int(match.group(3))
            loc_prf = 0  # Set to 0 for all records as requested
            weight = int(match.group(4))
            path_info = match.group(5).strip()
            
            # Extract AS path (remove origin code)
            path_parts = path_info.split()
            as_path = []
            for part in path_parts:
                if part.isdigit():
                    as_path.append(part)
            
            path = ' '.join(as_path) if as_path else ""
            
            route = {
                "network": network,
                "nextHop": next_hop,
                "metric": metric,
                "locPrf": loc_prf,
                "weight": weight,
                "path": path
            }
            routes.append(route)
    
    return {"routes": routes}


def get_bgp_routes_json():
    """
    Get BGP routes from sample data and return as JSON.
    
    Returns:
        str: JSON string of BGP routes
    """
    output_text = """IPv4
BGP table version is 0, local router ID is 169.254.0.185
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
            r RIB-failure, S Stale, R Removed
Origin codes: i - IGP, e - EGP, ? - incomplete

Network          Next Hop            Metric LocPrf Weight Path
*> 10.0.0.0         169.254.0.186          100             0 65100 ?
*> 10.2.0.0/16      169.254.0.185          100         32768 i
*> 10.5.0.0/16      169.254.0.185          100         32768 i
*> 10.6.0.0/16      169.254.0.185          100         32768 i
*> 10.10.0.0/16     169.254.0.185          100         32768 i
*> 10.42.0.0/16     169.254.0.185          100         32768 i
*> 10.56.0.0/16     169.254.0.185          100         32768 i
*> 10.133.0.0/21    169.254.0.185          100         32768 i
*> 10.192.2.0/23    169.254.0.186          100             0 65100 ?
*> 10.192.6.0/23    169.254.0.186          100             0 65100 ?
*> 10.208.0.0/18    169.254.0.185          100         32768 i
*> 10.210.0.0/20    169.254.0.186          100             0 65100 ?
*> 10.210.64.0/18   169.254.0.186          100             0 65100 ?
*> 10.210.128.0/20  169.254.0.186          100             0 65100 ?
*> 10.211.0.0/17    169.254.0.186          100             0 65100 ?
*> 10.211.128.0/17  169.254.0.186          100             0 65100 ?
*> 10.216.0.0/16    169.254.0.186          100             0 65100 ?
*> 10.224.64.0/19   169.254.0.185          100         32768 i
*> 10.227.128.0/18  169.254.0.185          100         32768 i
*> 10.227.192.0/18  169.254.0.185          100         32768 i
*> 10.228.64.0/18   169.254.0.185          100         32768 i
*> 10.228.128.0/18  169.254.0.185          100         32768 i
*> 10.228.192.0/18  169.254.0.185          100         32768 i
*> 10.229.64.0/18   169.254.0.185          100         32768 i
*> 10.229.128.0/18  169.254.0.185          100         32768 i
*> 10.229.192.0/18  169.254.0.185          100         32768 i
*> 10.230.0.0/18    169.254.0.185          100         32768 i
*> 10.230.64.0/18   169.254.0.185          100         32768 i
*> 10.230.128.0/18  169.254.0.185          100         32768 i
*> 10.230.192.0/18  169.254.0.185          100         32768 i
*> 10.246.48.0/20   169.254.0.185          100         32768 i
*> 10.254.192.0/18  169.254.0.185          100         32768 i
*> 10.255.0.0/18    169.254.0.185          100         32768 i
*> 10.255.64.0/18   169.254.0.185          100         32768 i
*> 10.255.128.0/18  169.254.0.185          100         32768 i
*> 10.255.192.0/19  169.254.0.185          100         32768 i
*> 10.255.224.0/19  169.254.0.185          100         32768 i
*> 100.64.0.64/27   169.254.0.185          100         32768 i
*> 100.64.0.96/27   169.254.0.185          100         32768 i
*> 100.64.0.128/27  169.254.0.185          100         32768 i
*> 100.64.0.160/27  169.254.0.185          100         32768 i
*> 172.16.0.0/12    169.254.0.186          100             0 65100 69999 21222 ?
*> 240.0.0.0/4      169.254.0.186          100             0 65100 69999 21222 ?
*> 253.128.0.0/14   169.254.0.186          100             0 65100 ?
*> 253.132.0.0/20   169.254.0.186          100             0 65100 ?

Total number of prefixes 45

IPv6
No BGP network exists"""
    
    # Parse the BGP output and return as JSON
    parsed_data = parse_bgp_routes(output_text)
    return json.dumps(parsed_data, indent=2)

def get_specific_network(prefix):
    # Get all BGP routes first
    all_routes = json.loads(get_bgp_routes_json())
    
    # Search through routes for matching prefix
    for route in all_routes["routes"]:
        if route["network"] == prefix:
            return route
            
    # Return None if no matching prefix is found
    return None

def main():
    """Main function to demonstrate the BGP parser."""
    print(get_bgp_routes_json())
    print(get_specific_network("10.42.0.0/16"))


if __name__ == "__main__":
    main()