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from pyalgs.algorithms.commons import util |
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from pyalgs.data_structures.commons.bag import Bag |
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View Code Duplication |
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class Graph(object): |
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V = 0 |
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adjList = None |
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def __init__(self, V): |
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self.V = V |
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self.adjList = [None] * V |
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for v in range(V): |
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self.adjList[v] = Bag() |
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def vertex_count(self): |
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return self.V |
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def adj(self, v): |
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return self.adjList[v].iterate() |
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def add_edge(self, v, w): |
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self.adjList[v].add(w) |
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self.adjList[w].add(v) |
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View Code Duplication |
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class Digraph(object): |
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V = 0 |
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adjList = None |
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def __init__(self, V): |
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self.V = V |
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self.adjList = [None] * V |
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for v in range(V): |
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self.adjList[v] = Bag() |
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def vertex_count(self): |
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return self.V |
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def adj(self, v): |
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return self.adjList[v].iterate() |
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def add_edge(self, v, w): |
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self.adjList[v].add(w) |
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def reverse(self): |
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g = Digraph(self.V) |
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for v in range(self.V): |
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for w in self.adjList[v].iterate(): |
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g.add_edge(w, v) |
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return g |
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class Edge(object): |
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v = None |
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w = None |
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weight = 0 |
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def __init__(self, v=None, w=None, weight=None): |
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if weight is None: |
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weight = 0 |
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self.v = v |
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self.w = w |
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self.weight = weight |
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def start(self): |
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return self.v |
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def end(self): |
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return self.w |
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def reverse(self): |
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return Edge(self.w, self.v, self.weight) |
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def either(self): |
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return self.v |
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def other(self, v): |
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if self.v == v: |
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return self.w |
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elif self.w == v: |
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return self.v |
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else: |
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raise ValueError('mismatched vertex detected') |
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# use for python 2 comparison |
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def __cmp__(self, other): |
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return util.cmp(self.weight, other.weight) |
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# user for python 3 comparison |
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def __lt__(self, other): |
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return util.less(self.weight, other.weight) |
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# user for python 3 comparison |
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def __gt__(self, other): |
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return util.greater(self.weight, other.weight) |
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def __str__(self): |
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return str(self.v) + ' =(' + str(self.weight) + ')=> ' + str(self.w) |
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class EdgeWeightedGraph(object): |
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adjList = None |
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V = 0 |
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def __init__(self, vertex_count): |
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self.V = vertex_count |
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self.adjList = [None] * vertex_count |
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for v in range(vertex_count): |
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self.adjList[v] = Bag() |
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def add_edge(self, edge): |
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v = edge.either() |
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w = edge.other(v) |
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self.adjList[v].add(edge) |
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self.adjList[w].add(edge) |
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def adj(self, v): |
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return self.adjList[v].iterate() |
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def vertex_count(self): |
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return self.V |
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def edges(self): |
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for v in range(self.V): |
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for e in self.adj(v): |
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if e.either() == v: |
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yield e |
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def to_graph(self): |
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g = Graph() |
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for e in self.edges(): |
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g.add_edge(e.start(), e.end()) |
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return g |
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def to_edge_weighted_digraph(self): |
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g = DirectedEdgeWeightedGraph(self.V) |
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for e in self.edges(): |
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g.add_edge(e) |
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g.add_edge(e.reverse()) |
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return g |
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class DirectedEdgeWeightedGraph(object): |
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adjList = None |
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V = 0 |
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def __init__(self, vertex_count): |
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self.V = vertex_count |
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self.adjList = [None] * vertex_count |
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for v in range(vertex_count): |
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self.adjList[v] = Bag() |
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def add_edge(self, edge): |
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v = edge.start() |
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self.adjList[v].add(edge) |
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def adj(self, v): |
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return self.adjList[v].iterate() |
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def vertex_count(self): |
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return self.V |
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def edges(self): |
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for v in range(self.V): |
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for e in self.adj(v): |
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yield e |
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def to_graph(self): |
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g = Graph() |
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for e in self.edges(): |
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g.add_edge(e.start(), e.end()) |
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return g |
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def to_digraph(self): |
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g = Digraph(self.V) |
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for e in self.edges(): |
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g.add_edge(e.start(), e.end()) |
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return g |
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class FlowEdge(object): |
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v = 0 |
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w = 0 |
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capacity = 0 |
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flow = 0 |
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def __init__(self, v, w, capacity): |
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self.v = v |
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self.w = w |
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self.capacity = capacity |
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def residual_capacity_to(self, end_v): |
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if self.w == end_v: |
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return self.capacity - self.flow |
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elif self.v == end_v: |
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return self.flow |
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else: |
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raise ValueError('end point not belong to flow edge') |
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def add_residual_flow_to(self, end_v, delta): |
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if self.v == end_v: |
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self.flow -= delta |
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elif self.w == end_v: |
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self.flow += delta |
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else: |
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raise ValueError('end point not belong to flow edge') |
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def start(self): |
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return self.v |
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def end(self): |
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return self.w |
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def other(self, x): |
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if x == self.v: |
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return self.w |
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else: |
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return self.v |
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def __str__(self): |
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return str(self.v) + ' =(' + str(self.capacity) + ', ' + str(self.flow) + ')=> ' + str(self.w) |
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class FlowNetwork(object): |
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V = None |
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adjList = None |
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def __init__(self, V): |
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self.V = V |
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self.adjList = [None] * V |
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for v in range(self.V): |
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self.adjList[v] = Bag() |
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def adj(self, v): |
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return self.adjList[v].iterate() |
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def add_edge(self, edge): |
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self.adjList[edge.start()].add(edge) |
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self.adjList[edge.end()].add(edge) |
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def vertex_count(self): |
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return self.V |
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def edges(self): |
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for v in range(self.V): |
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for e in self.adjList[v].iterate(): |
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if e.start() == v: |
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yield e |
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