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root/OpenMD/branches/development/src/brains/ForceManager.cpp
Revision: 1571
Committed: Fri May 27 16:45:44 2011 UTC (13 years, 11 months ago) by gezelter
File size: 18402 byte(s)
Log Message:
Added Atypes to new C++ force decomposition.

File Contents

# User Rev Content
1 gezelter 507 /*
2 gezelter 246 * Copyright (c) 2005 The University of Notre Dame. All Rights Reserved.
3     *
4     * The University of Notre Dame grants you ("Licensee") a
5     * non-exclusive, royalty free, license to use, modify and
6     * redistribute this software in source and binary code form, provided
7     * that the following conditions are met:
8     *
9 gezelter 1390 * 1. Redistributions of source code must retain the above copyright
10 gezelter 246 * notice, this list of conditions and the following disclaimer.
11     *
12 gezelter 1390 * 2. Redistributions in binary form must reproduce the above copyright
13 gezelter 246 * notice, this list of conditions and the following disclaimer in the
14     * documentation and/or other materials provided with the
15     * distribution.
16     *
17     * This software is provided "AS IS," without a warranty of any
18     * kind. All express or implied conditions, representations and
19     * warranties, including any implied warranty of merchantability,
20     * fitness for a particular purpose or non-infringement, are hereby
21     * excluded. The University of Notre Dame and its licensors shall not
22     * be liable for any damages suffered by licensee as a result of
23     * using, modifying or distributing the software or its
24     * derivatives. In no event will the University of Notre Dame or its
25     * licensors be liable for any lost revenue, profit or data, or for
26     * direct, indirect, special, consequential, incidental or punitive
27     * damages, however caused and regardless of the theory of liability,
28     * arising out of the use of or inability to use software, even if the
29     * University of Notre Dame has been advised of the possibility of
30     * such damages.
31 gezelter 1390 *
32     * SUPPORT OPEN SCIENCE! If you use OpenMD or its source code in your
33     * research, please cite the appropriate papers when you publish your
34     * work. Good starting points are:
35     *
36     * [1] Meineke, et al., J. Comp. Chem. 26, 252-271 (2005).
37     * [2] Fennell & Gezelter, J. Chem. Phys. 124, 234104 (2006).
38     * [3] Sun, Lin & Gezelter, J. Chem. Phys. 128, 24107 (2008).
39     * [4] Vardeman & Gezelter, in progress (2009).
40 gezelter 246 */
41    
42 gezelter 507 /**
43     * @file ForceManager.cpp
44     * @author tlin
45     * @date 11/09/2004
46     * @time 10:39am
47     * @version 1.0
48     */
49 gezelter 246
50     #include "brains/ForceManager.hpp"
51     #include "primitives/Molecule.hpp"
52 gezelter 1390 #define __OPENMD_C
53 gezelter 246 #include "utils/simError.h"
54 xsun 1215 #include "primitives/Bond.hpp"
55 tim 749 #include "primitives/Bend.hpp"
56 cli2 1275 #include "primitives/Torsion.hpp"
57     #include "primitives/Inversion.hpp"
58 gezelter 1551 #include "nonbonded/NonBondedInteraction.hpp"
59 gezelter 1549 #include "parallel/ForceMatrixDecomposition.hpp"
60 gezelter 1467
61 gezelter 1545 using namespace std;
62 gezelter 1390 namespace OpenMD {
63 gezelter 1469
64 gezelter 1545 ForceManager::ForceManager(SimInfo * info) : info_(info) {
65    
66 gezelter 1549 fDecomp_ = new ForceMatrixDecomposition(info_);
67 gezelter 1469 }
68 gezelter 1545
69 gezelter 1464 void ForceManager::calcForces() {
70 gezelter 1126
71 gezelter 1569 if (!info_->isTopologyDone()) {
72 gezelter 507 info_->update();
73 gezelter 1546 interactionMan_->setSimInfo(info_);
74     interactionMan_->initialize();
75     swfun_ = interactionMan_->getSwitchingFunction();
76 gezelter 1571 info_->prepareTopology();
77 gezelter 1549 fDecomp_->distributeInitialData();
78 gezelter 246 }
79 gezelter 1126
80 gezelter 1544 preCalculation();
81 gezelter 1546 shortRangeInteractions();
82     longRangeInteractions();
83 gezelter 1464 postCalculation();
84 tim 749
85 gezelter 507 }
86 gezelter 1126
87 gezelter 507 void ForceManager::preCalculation() {
88 gezelter 246 SimInfo::MoleculeIterator mi;
89     Molecule* mol;
90     Molecule::AtomIterator ai;
91     Atom* atom;
92     Molecule::RigidBodyIterator rbIter;
93     RigidBody* rb;
94 gezelter 1540 Molecule::CutoffGroupIterator ci;
95     CutoffGroup* cg;
96 gezelter 246
97     // forces are zeroed here, before any are accumulated.
98 chuckv 1245
99 gezelter 1126 for (mol = info_->beginMolecule(mi); mol != NULL;
100     mol = info_->nextMolecule(mi)) {
101 gezelter 507 for(atom = mol->beginAtom(ai); atom != NULL; atom = mol->nextAtom(ai)) {
102     atom->zeroForcesAndTorques();
103     }
104 chuckv 1245
105 gezelter 507 //change the positions of atoms which belong to the rigidbodies
106 gezelter 1126 for (rb = mol->beginRigidBody(rbIter); rb != NULL;
107     rb = mol->nextRigidBody(rbIter)) {
108 gezelter 507 rb->zeroForcesAndTorques();
109     }
110 gezelter 1540
111     if(info_->getNGlobalCutoffGroups() != info_->getNGlobalAtoms()){
112     for(cg = mol->beginCutoffGroup(ci); cg != NULL;
113     cg = mol->nextCutoffGroup(ci)) {
114     //calculate the center of mass of cutoff group
115     cg->updateCOM();
116     }
117     }
118 gezelter 246 }
119 gezelter 1540
120 gezelter 1126 // Zero out the stress tensor
121     tau *= 0.0;
122    
123 gezelter 507 }
124 gezelter 1126
125 gezelter 1546 void ForceManager::shortRangeInteractions() {
126 gezelter 246 Molecule* mol;
127     RigidBody* rb;
128     Bond* bond;
129     Bend* bend;
130     Torsion* torsion;
131 cli2 1275 Inversion* inversion;
132 gezelter 246 SimInfo::MoleculeIterator mi;
133     Molecule::RigidBodyIterator rbIter;
134     Molecule::BondIterator bondIter;;
135     Molecule::BendIterator bendIter;
136     Molecule::TorsionIterator torsionIter;
137 cli2 1275 Molecule::InversionIterator inversionIter;
138 tim 963 RealType bondPotential = 0.0;
139     RealType bendPotential = 0.0;
140     RealType torsionPotential = 0.0;
141 cli2 1275 RealType inversionPotential = 0.0;
142 gezelter 246
143     //calculate short range interactions
144 gezelter 1126 for (mol = info_->beginMolecule(mi); mol != NULL;
145     mol = info_->nextMolecule(mi)) {
146 gezelter 246
147 gezelter 507 //change the positions of atoms which belong to the rigidbodies
148 gezelter 1126 for (rb = mol->beginRigidBody(rbIter); rb != NULL;
149     rb = mol->nextRigidBody(rbIter)) {
150     rb->updateAtoms();
151 gezelter 507 }
152 gezelter 246
153 gezelter 1126 for (bond = mol->beginBond(bondIter); bond != NULL;
154     bond = mol->nextBond(bondIter)) {
155 tim 749 bond->calcForce();
156     bondPotential += bond->getPotential();
157 gezelter 507 }
158 gezelter 246
159 gezelter 1126 for (bend = mol->beginBend(bendIter); bend != NULL;
160     bend = mol->nextBend(bendIter)) {
161    
162     RealType angle;
163     bend->calcForce(angle);
164     RealType currBendPot = bend->getPotential();
165 gezelter 1448
166 gezelter 1126 bendPotential += bend->getPotential();
167 gezelter 1545 map<Bend*, BendDataSet>::iterator i = bendDataSets.find(bend);
168 gezelter 1126 if (i == bendDataSets.end()) {
169     BendDataSet dataSet;
170     dataSet.prev.angle = dataSet.curr.angle = angle;
171     dataSet.prev.potential = dataSet.curr.potential = currBendPot;
172     dataSet.deltaV = 0.0;
173 gezelter 1545 bendDataSets.insert(map<Bend*, BendDataSet>::value_type(bend, dataSet));
174 gezelter 1126 }else {
175     i->second.prev.angle = i->second.curr.angle;
176     i->second.prev.potential = i->second.curr.potential;
177     i->second.curr.angle = angle;
178     i->second.curr.potential = currBendPot;
179     i->second.deltaV = fabs(i->second.curr.potential -
180     i->second.prev.potential);
181     }
182 gezelter 507 }
183 gezelter 1126
184     for (torsion = mol->beginTorsion(torsionIter); torsion != NULL;
185     torsion = mol->nextTorsion(torsionIter)) {
186 tim 963 RealType angle;
187 gezelter 1126 torsion->calcForce(angle);
188 tim 963 RealType currTorsionPot = torsion->getPotential();
189 gezelter 1126 torsionPotential += torsion->getPotential();
190 gezelter 1545 map<Torsion*, TorsionDataSet>::iterator i = torsionDataSets.find(torsion);
191 gezelter 1126 if (i == torsionDataSets.end()) {
192     TorsionDataSet dataSet;
193     dataSet.prev.angle = dataSet.curr.angle = angle;
194     dataSet.prev.potential = dataSet.curr.potential = currTorsionPot;
195     dataSet.deltaV = 0.0;
196 gezelter 1545 torsionDataSets.insert(map<Torsion*, TorsionDataSet>::value_type(torsion, dataSet));
197 gezelter 1126 }else {
198     i->second.prev.angle = i->second.curr.angle;
199     i->second.prev.potential = i->second.curr.potential;
200     i->second.curr.angle = angle;
201     i->second.curr.potential = currTorsionPot;
202     i->second.deltaV = fabs(i->second.curr.potential -
203     i->second.prev.potential);
204     }
205     }
206 gezelter 1545
207 cli2 1275 for (inversion = mol->beginInversion(inversionIter);
208     inversion != NULL;
209     inversion = mol->nextInversion(inversionIter)) {
210     RealType angle;
211     inversion->calcForce(angle);
212     RealType currInversionPot = inversion->getPotential();
213     inversionPotential += inversion->getPotential();
214 gezelter 1545 map<Inversion*, InversionDataSet>::iterator i = inversionDataSets.find(inversion);
215 cli2 1275 if (i == inversionDataSets.end()) {
216     InversionDataSet dataSet;
217     dataSet.prev.angle = dataSet.curr.angle = angle;
218     dataSet.prev.potential = dataSet.curr.potential = currInversionPot;
219     dataSet.deltaV = 0.0;
220 gezelter 1545 inversionDataSets.insert(map<Inversion*, InversionDataSet>::value_type(inversion, dataSet));
221 cli2 1275 }else {
222     i->second.prev.angle = i->second.curr.angle;
223     i->second.prev.potential = i->second.curr.potential;
224     i->second.curr.angle = angle;
225     i->second.curr.potential = currInversionPot;
226     i->second.deltaV = fabs(i->second.curr.potential -
227     i->second.prev.potential);
228     }
229     }
230 gezelter 246 }
231    
232 gezelter 1126 RealType shortRangePotential = bondPotential + bendPotential +
233 cli2 1275 torsionPotential + inversionPotential;
234 gezelter 246 Snapshot* curSnapshot = info_->getSnapshotManager()->getCurrentSnapshot();
235     curSnapshot->statData[Stats::SHORT_RANGE_POTENTIAL] = shortRangePotential;
236 tim 665 curSnapshot->statData[Stats::BOND_POTENTIAL] = bondPotential;
237     curSnapshot->statData[Stats::BEND_POTENTIAL] = bendPotential;
238     curSnapshot->statData[Stats::DIHEDRAL_POTENTIAL] = torsionPotential;
239 gezelter 1545 curSnapshot->statData[Stats::INVERSION_POTENTIAL] = inversionPotential;
240 gezelter 507 }
241 gezelter 1126
242 gezelter 1546 void ForceManager::longRangeInteractions() {
243 gezelter 246
244 gezelter 1545 // some of this initial stuff will go away:
245     Snapshot* curSnapshot = info_->getSnapshotManager()->getCurrentSnapshot();
246     DataStorage* config = &(curSnapshot->atomData);
247     DataStorage* cgConfig = &(curSnapshot->cgData);
248     RealType* frc = config->getArrayPointer(DataStorage::dslForce);
249     RealType* pos = config->getArrayPointer(DataStorage::dslPosition);
250     RealType* trq = config->getArrayPointer(DataStorage::dslTorque);
251     RealType* A = config->getArrayPointer(DataStorage::dslAmat);
252     RealType* electroFrame = config->getArrayPointer(DataStorage::dslElectroFrame);
253     RealType* particlePot = config->getArrayPointer(DataStorage::dslParticlePot);
254     RealType* rc;
255    
256 gezelter 1540 if(info_->getNGlobalCutoffGroups() != info_->getNGlobalAtoms()){
257     rc = cgConfig->getArrayPointer(DataStorage::dslPosition);
258 gezelter 246 } else {
259 gezelter 1126 // center of mass of the group is the same as position of the atom
260     // if cutoff group does not exist
261 gezelter 507 rc = pos;
262 gezelter 246 }
263 gezelter 1126
264 gezelter 246 //initialize data before passing to fortran
265 gezelter 1550 RealType longRangePotential[N_INTERACTION_FAMILIES];
266 tim 963 RealType lrPot = 0.0;
267 gezelter 246 int isError = 0;
268    
269 gezelter 1550 // dangerous to iterate over enums, but we'll live on the edge:
270     for (int i = NO_FAMILY; i != N_INTERACTION_FAMILIES; ++i){
271 chuckv 664 longRangePotential[i]=0.0; //Initialize array
272     }
273 gezelter 1545
274     // new stuff starts here:
275    
276 gezelter 1549 fDecomp_->distributeData();
277 gezelter 1545
278 gezelter 1546 int cg1, cg2, atom1, atom2;
279     Vector3d d_grp, dag;
280 gezelter 1545 RealType rgrpsq, rgrp;
281 gezelter 1549 RealType vij;
282 gezelter 1545 Vector3d fij, fg;
283     pair<int, int> gtypes;
284     RealType rCutSq;
285     bool in_switching_region;
286     RealType sw, dswdr, swderiv;
287 gezelter 1549 vector<int> atomListColumn, atomListRow, atomListLocal;
288 gezelter 1545 InteractionData idat;
289 gezelter 1546 SelfData sdat;
290     RealType mf;
291 gezelter 1544
292 gezelter 1545 int loopStart, loopEnd;
293 gezelter 1544
294 gezelter 1545 loopEnd = PAIR_LOOP;
295 gezelter 1546 if (info_->requiresPrepair() ) {
296 gezelter 1545 loopStart = PREPAIR_LOOP;
297     } else {
298     loopStart = PAIR_LOOP;
299     }
300    
301     for (int iLoop = loopStart; iLoop < loopEnd; iLoop++) {
302    
303     if (iLoop == loopStart) {
304 gezelter 1549 bool update_nlist = fDecomp_->checkNeighborList();
305 gezelter 1545 if (update_nlist)
306 gezelter 1549 neighborList = fDecomp_->buildNeighborList();
307 gezelter 1544 }
308 gezelter 1545
309     for (vector<pair<int, int> >::iterator it = neighborList.begin();
310     it != neighborList.end(); ++it) {
311    
312     cg1 = (*it).first;
313     cg2 = (*it).second;
314    
315 gezelter 1549 gtypes = fDecomp_->getGroupTypes(cg1, cg2);
316     d_grp = fDecomp_->getIntergroupVector(cg1, cg2);
317 gezelter 1545 curSnapshot->wrapVector(d_grp);
318     rgrpsq = d_grp.lengthSquare();
319 gezelter 1546 rCutSq = groupCutoffMap[gtypes].first;
320 gezelter 1545
321     if (rgrpsq < rCutSq) {
322 gezelter 1554 *(idat.rcut) = groupCutoffMap[gtypes].second;
323 gezelter 1545 if (iLoop == PAIR_LOOP) {
324 gezelter 1546 vij *= 0.0;
325 gezelter 1545 fij = V3Zero;
326     }
327    
328 gezelter 1554 in_switching_region = swfun_->getSwitch(rgrpsq, *(idat.sw), dswdr,
329     rgrp);
330 gezelter 1549 atomListRow = fDecomp_->getAtomsInGroupRow(cg1);
331     atomListColumn = fDecomp_->getAtomsInGroupColumn(cg2);
332 gezelter 1545
333 gezelter 1549 for (vector<int>::iterator ia = atomListRow.begin();
334     ia != atomListRow.end(); ++ia) {
335 gezelter 1545 atom1 = (*ia);
336    
337 gezelter 1549 for (vector<int>::iterator jb = atomListColumn.begin();
338     jb != atomListColumn.end(); ++jb) {
339 gezelter 1545 atom2 = (*jb);
340    
341 gezelter 1549 if (!fDecomp_->skipAtomPair(atom1, atom2)) {
342 gezelter 1545
343 gezelter 1549 idat = fDecomp_->fillInteractionData(atom1, atom2);
344 gezelter 1546
345 gezelter 1549 if (atomListRow.size() == 1 && atomListColumn.size() == 1) {
346 gezelter 1554 *(idat.d) = d_grp;
347     *(idat.r2) = rgrpsq;
348 gezelter 1545 } else {
349 gezelter 1554 *(idat.d) = fDecomp_->getInteratomicVector(atom1, atom2);
350     curSnapshot->wrapVector( *(idat.d) );
351     *(idat.r2) = idat.d->lengthSquare();
352 gezelter 1545 }
353    
354 gezelter 1554 *(idat.rij) = sqrt( *(idat.r2) );
355 gezelter 1546
356 gezelter 1545 if (iLoop == PREPAIR_LOOP) {
357     interactionMan_->doPrePair(idat);
358     } else {
359     interactionMan_->doPair(idat);
360 gezelter 1554 vij += *(idat.vpair);
361     fij += *(idat.f1);
362     tau -= outProduct( *(idat.d), *(idat.f1));
363 gezelter 1545 }
364     }
365     }
366     }
367    
368     if (iLoop == PAIR_LOOP) {
369     if (in_switching_region) {
370     swderiv = vij * dswdr / rgrp;
371     fg = swderiv * d_grp;
372    
373     fij += fg;
374    
375 gezelter 1549 if (atomListRow.size() == 1 && atomListColumn.size() == 1) {
376 gezelter 1554 tau -= outProduct( *(idat.d), fg);
377 gezelter 1545 }
378    
379 gezelter 1549 for (vector<int>::iterator ia = atomListRow.begin();
380     ia != atomListRow.end(); ++ia) {
381 gezelter 1545 atom1 = (*ia);
382 gezelter 1569 mf = fDecomp_->getMassFactorRow(atom1);
383 gezelter 1545 // fg is the force on atom ia due to cutoff group's
384     // presence in switching region
385     fg = swderiv * d_grp * mf;
386 gezelter 1549 fDecomp_->addForceToAtomRow(atom1, fg);
387 gezelter 1545
388 gezelter 1549 if (atomListRow.size() > 1) {
389 gezelter 1546 if (info_->usesAtomicVirial()) {
390 gezelter 1545 // find the distance between the atom
391     // and the center of the cutoff group:
392 gezelter 1549 dag = fDecomp_->getAtomToGroupVectorRow(atom1, cg1);
393 gezelter 1545 tau -= outProduct(dag, fg);
394     }
395     }
396     }
397 gezelter 1549 for (vector<int>::iterator jb = atomListColumn.begin();
398     jb != atomListColumn.end(); ++jb) {
399 gezelter 1545 atom2 = (*jb);
400 gezelter 1569 mf = fDecomp_->getMassFactorColumn(atom2);
401 gezelter 1545 // fg is the force on atom jb due to cutoff group's
402     // presence in switching region
403     fg = -swderiv * d_grp * mf;
404 gezelter 1549 fDecomp_->addForceToAtomColumn(atom2, fg);
405 gezelter 1545
406 gezelter 1549 if (atomListColumn.size() > 1) {
407 gezelter 1546 if (info_->usesAtomicVirial()) {
408 gezelter 1545 // find the distance between the atom
409     // and the center of the cutoff group:
410 gezelter 1549 dag = fDecomp_->getAtomToGroupVectorColumn(atom2, cg2);
411 gezelter 1545 tau -= outProduct(dag, fg);
412     }
413     }
414     }
415     }
416     //if (!SIM_uses_AtomicVirial) {
417     // tau -= outProduct(d_grp, fij);
418     //}
419     }
420     }
421     }
422    
423     if (iLoop == PREPAIR_LOOP) {
424 gezelter 1546 if (info_->requiresPrepair()) {
425 gezelter 1549 fDecomp_->collectIntermediateData();
426 gezelter 1570
427     for (int atom1 = 0; atom1 < info_->getNAtoms(); atom1++) {
428 gezelter 1549 sdat = fDecomp_->fillSelfData(atom1);
429 gezelter 1545 interactionMan_->doPreForce(sdat);
430     }
431 gezelter 1570
432 gezelter 1549 fDecomp_->distributeIntermediateData();
433 gezelter 1545 }
434     }
435    
436 gezelter 1544 }
437 gezelter 1545
438 gezelter 1549 fDecomp_->collectData();
439 gezelter 1545
440 gezelter 1570 if ( info_->requiresSkipCorrection() ) {
441    
442     for (int atom1 = 0; atom1 < fDecomp_->getNAtomsInRow(); atom1++) {
443 gezelter 1544
444 gezelter 1570 vector<int> skipList = fDecomp_->getSkipsForRowAtom( atom1 );
445    
446     for (vector<int>::iterator jb = skipList.begin();
447     jb != skipList.end(); ++jb) {
448    
449     atom2 = (*jb);
450     idat = fDecomp_->fillSkipData(atom1, atom2);
451     interactionMan_->doSkipCorrection(idat);
452    
453 gezelter 1545 }
454     }
455 gezelter 246 }
456 gezelter 1570
457     if (info_->requiresSelfCorrection()) {
458 gezelter 1545
459 gezelter 1570 for (int atom1 = 0; atom1 < info_->getNAtoms(); atom1++) {
460     sdat = fDecomp_->fillSelfData(atom1);
461     interactionMan_->doSelfCorrection(sdat);
462     }
463    
464     }
465    
466 gezelter 1550 // dangerous to iterate over enums, but we'll live on the edge:
467     for (int i = NO_FAMILY; i != N_INTERACTION_FAMILIES; ++i){
468 chuckv 664 lrPot += longRangePotential[i]; //Quick hack
469     }
470 gezelter 1503
471 gezelter 246 //store the tau and long range potential
472 chuckv 664 curSnapshot->statData[Stats::LONG_RANGE_POTENTIAL] = lrPot;
473 gezelter 1550 curSnapshot->statData[Stats::VANDERWAALS_POTENTIAL] = longRangePotential[VANDERWAALS_FAMILY];
474     curSnapshot->statData[Stats::ELECTROSTATIC_POTENTIAL] = longRangePotential[ELECTROSTATIC_FAMILY];
475 gezelter 507 }
476 gezelter 246
477 gezelter 1126
478 gezelter 1464 void ForceManager::postCalculation() {
479 gezelter 246 SimInfo::MoleculeIterator mi;
480     Molecule* mol;
481     Molecule::RigidBodyIterator rbIter;
482     RigidBody* rb;
483 gezelter 1126 Snapshot* curSnapshot = info_->getSnapshotManager()->getCurrentSnapshot();
484 gezelter 246
485     // collect the atomic forces onto rigid bodies
486 gezelter 1126
487     for (mol = info_->beginMolecule(mi); mol != NULL;
488     mol = info_->nextMolecule(mi)) {
489     for (rb = mol->beginRigidBody(rbIter); rb != NULL;
490     rb = mol->nextRigidBody(rbIter)) {
491 gezelter 1464 Mat3x3d rbTau = rb->calcForcesAndTorquesAndVirial();
492     tau += rbTau;
493 gezelter 507 }
494 gezelter 1126 }
495 gezelter 1464
496 gezelter 1126 #ifdef IS_MPI
497 gezelter 1464 Mat3x3d tmpTau(tau);
498     MPI_Allreduce(tmpTau.getArrayPointer(), tau.getArrayPointer(),
499     9, MPI_REALTYPE, MPI_SUM, MPI_COMM_WORLD);
500 gezelter 1126 #endif
501 gezelter 1464 curSnapshot->statData.setTau(tau);
502 gezelter 507 }
503 gezelter 246
504 gezelter 1390 } //end namespace OpenMD

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