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Serializing Oriented Weighted Graphics

I have a directed weighted graph. Each node of the graph is represented as 2-tuples, the first element of which is the name node, and the second element is a tuple containing all the vertices originating from this node, ordered by their weight. Basically, the weight of each vertex is its index inside this set.

Exempli gratia:

a = ('A', () )

a is a node named A, where vertices do not come from.

b = ('B', () )
a = ('A', (b,) )

a is a node named A with one vertex to a node named B with a weight of 0.

b = ('B', () )
c = ('C', () )
a = ('A', (b, c) )

a is a node named A with two vertices to nodes named B and C, the first of weight 0 and the second of weight 1.

Obviously ('A', (b, c) )not equal ('A', (c, b) ).

Now I need to serialize this graph according to these rules:

  • The first element of the result is the starting node.
  • , node . node , .
  • .

, (), .

:

f = ('F', () )
e = ('E', () )
d = ('D', (e,) )
c = ('C', (f, d, e) )
b = ('B', (d,) )
a = ('A', (b, c) )

:

['A', 'B', 'C', 'D', 'F', 'E']

:

def serialize (node):
    acc = []

    def serializeRec (node, level):
        tbd = [] #acc items to be deleted
        tbi = False #insertion index
        for idx, item in enumerate (acc):
            if item [1] > level and tbi == False:
                tbi = idx
            if item [0] == node [0]:
                if item [1] > level: tbd.append (item)
                else: break
        else:
            if tbi == False: acc.append ( (node [0], level) )
            else: acc.insert (tbi, (node [0], level) )
        for item in tbd:
            acc.remove (item)
        for vertex in node [1]:
            serializeRec (vertex, level + 1)

    serializeRec (node, 0)
    #remove levels
    return [node for node, level in acc]

, -, , . :

def serializeDict (node):
    levels = defaultdict (list) #nodes on each level
    nodes = {} #on which level is which node

    def serializeRec (node, level):
        try:
            curLevel = nodes [node [0] ]
            if curLevel > level:
                nodes [node [0] ] = level
                levels [curLevel].remove (node [0] )
                levels [level].append (node [0] )
        except:
            nodes [node [0] ] = level
            levels [level].append (node [0] )
        for vertex in node [1]:
            serializeRec (vertex, level + 1)

    serializeRec (node, 0)
    #flatten dict items
    return [node for level in (v for _, v in sorted (levels.items (), key = lambda x: x [0] ) ) for node in level]

, .

:

?

(, ), KLOC , . , . , .

TL, DR .

:

z = ('Z', () ); y = ('Y', (z,) ); x = ('X', (z, y) ); w = ('W', (x, y, z) ); v = ('V', (w, x) ); u = ('U', (w, v) ); t = ('T', (u, w) ); s = ('S', (z, v, u) ); r = ('R', (t, u, z) ); q = ('Q', (r, z) ); p = ('P', (w, u) ); o = ('O', (v, r, q) ); n = ('N', (r, z) ); m = ('M', (t,) ); l = ('L', (r,) ); k = ('K', (x, v) ); j = ('J', (u,) ); i = ('I', (n, k) ); h = ('H', (k, x) ); g = ('G', (l,) ); f = ('F', (t, m) ); e = ('E', (u,) ); d = ('D', (t, e, v) ); c = ('C', (m,) ); b = ('B', (n,) ); a = ('A', (g, m, v) )
+4
2

:

from collections import deque

def serialize_plain(n):
    name, children = n
    output = [name]

    candidates = deque(children)
    while candidates:
        cname, cchildren = candidates.popleft()
        if cname not in output:
            output.append(cname)
            candidates.extend(cchildren)

    return output

, , , , :

from collections import deque

def serialize_with_set(n):
    name, children = n
    output = [name]
    done = {name}

    candidates = deque(children)
    while candidates:
        cname, cchildren = candidates.popleft()
        if cname not in done:
            output.append(cname)
            done.add(cname)
            candidates.extend(cchildren)

    return output
+1

:

node. , node . node , . .

, , Breadth First Traversal, . , , .

Breadth First Traversal , . , ,, , ++ boost::graph, ++.

0

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