r233:28239207a8a3
Wed, 23 Jul 2008 19:32:48
[Not Reviewed]
0 comments (0 inline)
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@@ -1171,11 +1171,11 @@ |
| 1171 | 1171 |
///Dynamic arc look up between given endpoints. |
| 1172 | 1172 |
|
| 1173 | 1173 |
///Using this class, you can find an arc in a digraph from a given |
| 1174 |
///source to a given target in amortized time <em>O(log |
|
| 1174 |
///source to a given target in amortized time <em>O(log</em>d<em>)</em>, |
|
| 1175 | 1175 |
///where <em>d</em> is the out-degree of the source node. |
| 1176 | 1176 |
/// |
| 1177 | 1177 |
///It is possible to find \e all parallel arcs between two nodes with |
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///the \c |
|
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///the \c operator() member. |
|
| 1179 | 1179 |
/// |
| 1180 | 1180 |
///See the \ref ArcLookUp and \ref AllArcLookUp classes if your |
| 1181 | 1181 |
///digraph is not changed so frequently. |
| ... | ... |
@@ -1423,8 +1423,8 @@ |
| 1423 | 1423 |
void refresh() {
|
| 1424 | 1424 |
for(NodeIt n(_g);n!=INVALID;++n) {
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| 1425 | 1425 |
std::vector<Arc> v; |
| 1426 |
for(OutArcIt e(_g,n);e!=INVALID;++e) v.push_back(e); |
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if(v.size()) {
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for(OutArcIt a(_g,n);a!=INVALID;++a) v.push_back(a); |
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if (!v.empty()) {
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|
| 1428 | 1428 |
std::sort(v.begin(),v.end(),ArcLess(_g)); |
| 1429 | 1429 |
Arc head = refreshRec(v,0,v.size()-1); |
| 1430 | 1430 |
_head.set(n, head); |
| ... | ... |
@@ -1506,49 +1506,36 @@ |
| 1506 | 1506 |
|
| 1507 | 1507 |
///Find an arc between two nodes. |
| 1508 | 1508 |
|
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///Find an arc between two nodes in time <em>O(</em>log<em>d)</em>, where |
|
| 1510 |
/// <em>d</em> is the number of outgoing arcs of \c s. |
|
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///Find an arc between two nodes. |
|
| 1511 | 1510 |
///\param s The source node |
| 1512 | 1511 |
///\param t The target node |
| 1513 |
///\return An arc from \c s to \c t if there exists, |
|
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///\ref INVALID otherwise. |
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Arc operator()(Node s, Node t) const |
|
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{
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Arc a = _head[s]; |
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if (a == INVALID) return INVALID; |
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| 1519 |
while (true) {
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if (_g.target(a) == t) {
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|
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const_cast<DynArcLookUp&>(*this).splay(a); |
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return a; |
|
| 1523 |
} else if (t < _g.target(a)) {
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|
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if (_left[a] == INVALID) {
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const_cast<DynArcLookUp&>(*this).splay(a); |
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| 1526 |
return INVALID; |
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} else {
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a = _left[a]; |
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} |
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} else {
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if (_right[a] == INVALID) {
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const_cast<DynArcLookUp&>(*this).splay(a); |
|
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return INVALID; |
|
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} else {
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| 1535 |
a = _right[a]; |
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} |
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} |
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} |
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} |
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| 1540 |
|
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///Find the first arc between two nodes. |
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|
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///Find the first arc between two nodes in time |
|
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/// <em>O(</em>log<em>d)</em>, where <em>d</em> is the number of |
|
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/// outgoing arcs of \c s. |
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///\param s The source node |
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///\param t The target node |
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///\return An arc from \c s to \c t if there exists, \ref INVALID |
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/// otherwise. |
|
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Arc findFirst(Node s, Node t) const |
|
| 1551 |
|
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///\param p The previous arc between \c s and \c t. It it is INVALID or |
|
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///not given, the operator finds the first appropriate arc. |
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///\return An arc from \c s to \c t after \c p or |
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///\ref INVALID if there is no more. |
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/// |
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///For example, you can count the number of arcs from \c u to \c v in the |
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| 1518 |
///following way. |
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///\code |
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///DynArcLookUp<ListDigraph> ae(g); |
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///... |
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///int n=0; |
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///for(Arc e=ae(u,v);e!=INVALID;e=ae(u,v,e)) n++; |
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///\endcode |
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/// |
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///Finding the arcs take at most <em>O(</em>log<em>d)</em> |
|
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///amortized time, specifically, the time complexity of the lookups |
|
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///is equal to the optimal search tree implementation for the |
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///current query distribution in a constant factor. |
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/// |
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///\note This is a dynamic data structure, therefore the data |
|
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///structure is updated after each graph alteration. However, |
|
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///theoretically this data structure is faster than \c ArcLookUp |
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///or AllEdgeLookup, but it often provides worse performance than |
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///them. |
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/// |
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Arc operator()(Node s, Node t, Arc p = INVALID) const {
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|
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if (p == INVALID) {
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|
| 1552 | 1539 |
Arc a = _head[s]; |
| 1553 | 1540 |
if (a == INVALID) return INVALID; |
| 1554 | 1541 |
Arc r = INVALID; |
| ... | ... |
@@ -1572,26 +1559,8 @@ |
| 1572 | 1559 |
} |
| 1573 | 1560 |
} |
| 1574 | 1561 |
} |
| 1575 |
} |
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| 1576 |
|
|
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///Find the next arc between two nodes. |
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|
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///Find the next arc between two nodes in time |
|
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/// <em>O(</em>log<em>d)</em>, where <em>d</em> is the number of |
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/// outgoing arcs of \c s. |
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///\param s The source node |
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| 1583 |
///\param t The target node |
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///\return An arc from \c s to \c t if there exists, \ref INVALID |
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/// otherwise. |
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|
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///\note If \c e is not the result of the previous \c findFirst() |
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///operation then the amorized time bound can not be guaranteed. |
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#ifdef DOXYGEN |
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Arc findNext(Node s, Node t, Arc a) const |
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#else |
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Arc findNext(Node, Node t, Arc a) const |
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#endif |
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{
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} else {
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| 1563 |
Arc a = p; |
|
| 1595 | 1564 |
if (_right[a] != INVALID) {
|
| 1596 | 1565 |
a = _right[a]; |
| 1597 | 1566 |
while (_left[a] != INVALID) {
|
| ... | ... |
@@ -1612,6 +1581,7 @@ |
| 1612 | 1581 |
if (_g.target(a) == t) return a; |
| 1613 | 1582 |
else return INVALID; |
| 1614 | 1583 |
} |
| 1584 |
} |
|
| 1615 | 1585 |
|
| 1616 | 1586 |
}; |
| 1617 | 1587 |
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