From 894d95fc11f579361cde033d86b9c2a1400ae37c Mon Sep 17 00:00:00 2001
From: David Rosca <roscadav@fit.cvut.cz>
Date: Sun, 8 Mar 2015 09:42:20 +0100
Subject: [PATCH] DFS: Add version returning predecessors and opening/closing
times
Also simplify lambdas in tests to capture everything
---
alib2algo/src/graph/traverse/Dfs.cpp | 66 ++++++++++++--
alib2algo/src/graph/traverse/Dfs.h | 3 +
alib2algo/test-src/graph/traverse/DfsTest.cpp | 88 +++++++++++++++++--
alib2algo/test-src/graph/traverse/DfsTest.h | 2 +
4 files changed, 142 insertions(+), 17 deletions(-)
diff --git a/alib2algo/src/graph/traverse/Dfs.cpp b/alib2algo/src/graph/traverse/Dfs.cpp
index 30f00d3ce8..dda9f51b1f 100644
--- a/alib2algo/src/graph/traverse/Dfs.cpp
+++ b/alib2algo/src/graph/traverse/Dfs.cpp
@@ -13,6 +13,7 @@ struct Data
{
Node start;
std::function<bool(const Node&)> func;
+ std::function<void(const Node&, const Node&, int, int)> func2;
};
template <typename T>
@@ -22,23 +23,48 @@ static void dfs_impl(const T &graph, const Node &start, std::function<bool(const
std::stack<Node> s;
s.push(start);
+ visited[start] = true;
+
while (!s.empty()) {
Node n = s.top(); s.pop();
- if (visited.find(n) == visited.end()) {
- if (!func(n)) {
- return;
- }
- visited.insert({n, true});
- for (const Node &e : graph.neighbors(n)) {
+
+ if (!func(n)) {
+ return;
+ }
+
+ for (const Node &e : graph.neighbors(n)) {
+ if (visited.find(e) == visited.end()) {
+ visited[e] = true;
s.push(e);
}
}
}
}
+template <typename T>
+static void dfs2_impl(const T &graph, const Node &n, const Node &p, std::unordered_map<Node, bool> &visited, int &time, std::function<void(const Node&, const Node&, int, int)> func)
+{
+ int opened = ++time;
+ visited[n] = true;
+
+ for (const Node &e : graph.neighbors(n)) {
+ if (visited.find(e) == visited.end()) {
+ dfs2_impl(graph, e, n, visited, time, func);
+ }
+ }
+
+ func(n, p, opened, ++time);
+}
+
void Dfs::dfs(const Graph &graph, const Node &start, std::function<bool(const Node&)> func)
{
- Data data = { start, func };
+ Data data = { start, func, nullptr };
+ graph.getData().Accept(static_cast<void*>(&data), DFS);
+}
+
+void Dfs::dfs(const Graph &graph, const Node &start, std::function<void(const Node&, const Node&, int, int)> func)
+{
+ Data data = { start, nullptr, func };
graph.getData().Accept(static_cast<void*>(&data), DFS);
}
@@ -47,21 +73,43 @@ void Dfs::dfs(const DirectedGraph &graph, const Node &start, std::function<bool(
dfs_impl(graph, start, func);
}
+void Dfs::dfs(const DirectedGraph &graph, const Node &start, std::function<void(const Node&, const Node&, int, int)> func)
+{
+ int time = 0;
+ std::unordered_map<Node, bool> visited;
+ dfs2_impl(graph, start, Node(), visited, time, func);
+}
+
void Dfs::dfs(const UndirectedGraph &graph, const Node &start, std::function<bool(const Node&)> func)
{
dfs_impl(graph, start, func);
}
+void Dfs::dfs(const UndirectedGraph &graph, const Node &start, std::function<void(const Node&, const Node&, int, int)> func)
+{
+ int time = 0;
+ std::unordered_map<Node, bool> visited;
+ dfs2_impl(graph, start, Node(), visited, time, func);
+}
+
void Dfs::Visit(void *data, const DirectedGraph &graph) const
{
Data d = *static_cast<Data*>(data);
- dfs(graph, d.start, d.func);
+ if (d.func) {
+ dfs(graph, d.start, d.func);
+ } else if (d.func2) {
+ dfs(graph, d.start, d.func2);
+ }
}
void Dfs::Visit(void *data, const UndirectedGraph &graph) const
{
Data d = *static_cast<Data*>(data);
- dfs(graph, d.start, d.func);
+ if (d.func) {
+ dfs(graph, d.start, d.func);
+ } else if (d.func2) {
+ dfs(graph, d.start, d.func2);
+ }
}
const Dfs Dfs::DFS;
diff --git a/alib2algo/src/graph/traverse/Dfs.h b/alib2algo/src/graph/traverse/Dfs.h
index 85fa390ba3..bc45c5de49 100644
--- a/alib2algo/src/graph/traverse/Dfs.h
+++ b/alib2algo/src/graph/traverse/Dfs.h
@@ -16,9 +16,12 @@ class Dfs : public graph::VisitableGraphBase::const_visitor_type
{
public:
static void dfs(const Graph &graph, const Node &start, std::function<bool(const Node&)> func);
+ static void dfs(const Graph &graph, const Node &start, std::function<void(const Node&, const Node&, int, int)> func);
static void dfs(const DirectedGraph &graph, const Node &start, std::function<bool(const Node&)> func);
+ static void dfs(const DirectedGraph &graph, const Node &start, std::function<void(const Node&, const Node&, int, int)> func);
static void dfs(const UndirectedGraph &graph, const Node &start, std::function<bool(const Node&)> func);
+ static void dfs(const UndirectedGraph &graph, const Node &start, std::function<void(const Node&, const Node&, int, int)> func);
private:
void Visit(void *data, const DirectedGraph &graph) const;
diff --git a/alib2algo/test-src/graph/traverse/DfsTest.cpp b/alib2algo/test-src/graph/traverse/DfsTest.cpp
index f4c8071e83..32541be9b9 100644
--- a/alib2algo/test-src/graph/traverse/DfsTest.cpp
+++ b/alib2algo/test-src/graph/traverse/DfsTest.cpp
@@ -26,7 +26,7 @@ void GraphDfsTest::testTraverseAll()
dg.addEdge(graph::DirectedEdge(n4, n5));
counter = 0;
- graph::traverse::Dfs::dfs(dg, n1, [&counter](const graph::Node &) {
+ graph::traverse::Dfs::dfs(dg, n1, [&](const graph::Node &) {
counter++;
return true;
});
@@ -44,7 +44,7 @@ void GraphDfsTest::testTraverseAll()
ug.addEdge(graph::UndirectedEdge(n4, n5));
counter = 0;
- graph::traverse::Dfs::dfs(ug, n1, [&counter](const graph::Node &) {
+ graph::traverse::Dfs::dfs(ug, n1, [&](const graph::Node &) {
counter++;
return true;
});
@@ -69,7 +69,7 @@ void GraphDfsTest::testEarlyReturn()
dg.addEdge(graph::DirectedEdge(n3, n4));
counter = 0;
- graph::traverse::Dfs::dfs(dg, n1, [&counter](const graph::Node &) {
+ graph::traverse::Dfs::dfs(dg, n1, [&](const graph::Node &) {
counter++;
if (counter == 2) {
return false;
@@ -87,7 +87,7 @@ void GraphDfsTest::testEarlyReturn()
ug.addEdge(graph::UndirectedEdge(n3, n4));
counter = 0;
- graph::traverse::Dfs::dfs(ug, n1, [&counter](const graph::Node &) {
+ graph::traverse::Dfs::dfs(ug, n1, [&](const graph::Node &) {
counter++;
if (counter == 2) {
return false;
@@ -117,7 +117,7 @@ void GraphDfsTest::testDisconnectedGraph()
dg.addEdge(graph::DirectedEdge(n3, n4));
counter = 0;
- graph::traverse::Dfs::dfs(dg, n1, [&counter](const graph::Node &) {
+ graph::traverse::Dfs::dfs(dg, n1, [&](const graph::Node &) {
counter++;
return true;
});
@@ -125,7 +125,7 @@ void GraphDfsTest::testDisconnectedGraph()
CPPUNIT_ASSERT_EQUAL(4, counter);
counter = 0;
- graph::traverse::Dfs::dfs(dg, n5, [&counter](const graph::Node &) {
+ graph::traverse::Dfs::dfs(dg, n5, [&](const graph::Node &) {
counter++;
return true;
});
@@ -141,7 +141,7 @@ void GraphDfsTest::testDisconnectedGraph()
ug.addEdge(graph::UndirectedEdge(n3, n4));
counter = 0;
- graph::traverse::Dfs::dfs(ug, n1, [&counter](const graph::Node &) {
+ graph::traverse::Dfs::dfs(ug, n1, [&](const graph::Node &) {
counter++;
return true;
});
@@ -149,10 +149,82 @@ void GraphDfsTest::testDisconnectedGraph()
CPPUNIT_ASSERT_EQUAL(4, counter);
counter = 0;
- graph::traverse::Dfs::dfs(ug, n5, [&counter](const graph::Node &) {
+ graph::traverse::Dfs::dfs(ug, n5, [&](const graph::Node &) {
counter++;
return true;
});
CPPUNIT_ASSERT_EQUAL(1, counter);
}
+
+void GraphDfsTest::testDfs2()
+{
+ // Common
+ int counter;
+ std::unordered_map<graph::Node, int> opened;
+ std::unordered_map<graph::Node, int> closed;
+ std::unordered_map<graph::Node, graph::Node> predecessors;
+
+ graph::Node n1("n1");
+ graph::Node n2("n2");
+ graph::Node n3("n3");
+ graph::Node n4("n4");
+ graph::Node n5("n5");
+
+ // Directed
+ graph::DirectedGraph dg;
+ dg.addEdge(graph::DirectedEdge(n1, n2));
+ dg.addEdge(graph::DirectedEdge(n1, n3));
+ dg.addEdge(graph::DirectedEdge(n1, n4));
+ dg.addEdge(graph::DirectedEdge(n2, n5));
+
+ counter = 0;
+ opened.clear();
+ closed.clear();
+ predecessors.clear();
+
+ graph::traverse::Dfs::dfs(dg, n1, [&](const graph::Node &n, const graph::Node &p, int o, int c) {
+ counter++;
+ opened[n] = o;
+ closed[n] = c;
+ predecessors[n] = p;
+ });
+
+ CPPUNIT_ASSERT_EQUAL(5, counter);
+ CPPUNIT_ASSERT_EQUAL(4, closed[n5]);
+
+ CPPUNIT_ASSERT_EQUAL(graph::Node(), predecessors[n1]);
+ CPPUNIT_ASSERT_EQUAL(n1, predecessors[n2]);
+ CPPUNIT_ASSERT_EQUAL(n1, predecessors[n3]);
+ CPPUNIT_ASSERT_EQUAL(n1, predecessors[n4]);
+ CPPUNIT_ASSERT_EQUAL(n2, predecessors[n5]);
+
+ // Undirected
+ graph::UndirectedGraph ug;
+ ug.addEdge(graph::UndirectedEdge(n1, n2));
+ ug.addEdge(graph::UndirectedEdge(n1, n3));
+ ug.addEdge(graph::UndirectedEdge(n1, n4));
+ ug.addEdge(graph::UndirectedEdge(n2, n5));
+
+ counter = 0;
+ opened.clear();
+ closed.clear();
+ predecessors.clear();
+
+ graph::traverse::Dfs::dfs(ug, n1, [&](const graph::Node &n, const graph::Node &p, int o, int c) {
+ counter++;
+ opened[n] = o;
+ closed[n] = c;
+ predecessors[n] = p;
+ });
+
+ CPPUNIT_ASSERT_EQUAL(5, counter);
+ CPPUNIT_ASSERT_EQUAL(4, closed[n5]);
+
+ CPPUNIT_ASSERT_EQUAL(graph::Node(), predecessors[n1]);
+ CPPUNIT_ASSERT_EQUAL(n1, predecessors[n2]);
+ CPPUNIT_ASSERT_EQUAL(n1, predecessors[n3]);
+ CPPUNIT_ASSERT_EQUAL(n1, predecessors[n4]);
+ CPPUNIT_ASSERT_EQUAL(n2, predecessors[n5]);
+}
+
diff --git a/alib2algo/test-src/graph/traverse/DfsTest.h b/alib2algo/test-src/graph/traverse/DfsTest.h
index c3bf1350e4..280368070a 100644
--- a/alib2algo/test-src/graph/traverse/DfsTest.h
+++ b/alib2algo/test-src/graph/traverse/DfsTest.h
@@ -9,12 +9,14 @@ class GraphDfsTest : public CppUnit::TestFixture
CPPUNIT_TEST(testTraverseAll);
CPPUNIT_TEST(testEarlyReturn);
CPPUNIT_TEST(testDisconnectedGraph);
+ CPPUNIT_TEST(testDfs2);
CPPUNIT_TEST_SUITE_END();
public:
void testTraverseAll();
void testEarlyReturn();
void testDisconnectedGraph();
+ void testDfs2();
};
#endif // DFS_TEST_H_
--
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