//prev map is excellent
vector<vector<string> > findLadders(string start, string end, unordered_set<string> &dict) {
vector<vector<string> > result;
vector<string> ret;
unordered_map<string, unordered_set<string> > prevMap;
vector<unordered_set<string> > candidates(2);
candidates[0].insert(start);
while (true) {
/* for (auto it = candidates[0].begin(); it != candidates[0].end(); it ++) {*/
//cout << *it << " ";
//}
//cout << endl;
//for (auto it = dict.begin(); it != dict.end(); it ++) {
//cout << *it << " ";
//}
/*cout << endl;*/
for (auto it = candidates[0].begin(); it != candidates[0].end(); it ++) {
dict.erase(*it);
}
candidates[1].clear();
for (auto it = candidates[0].begin(); it != candidates[0].end(); it ++) {
for (int i = 0; i < (int) it->length(); i ++) {
string word = *it;
for (char j = 'a'; j <= 'z'; j ++) {
if (word[i] == j) {
continue;
}
word[i] = j;
if (dict.find(word) != dict.end()) {
prevMap[word].insert(*it);
candidates[1].insert(word);
}
if (word == end) {
prevMap[word].insert(*it);
candidates[1].insert(word);
}
}
}
}
if (candidates[1].empty()) {
return result;
}
if (candidates[1].count(end)) {
break;
}
candidates[0].swap(candidates[1]);
}
cout << "f**k" << endl;
generateResult(prevMap, ret, end, result);
return result;
}
void generateResult(unordered_map<string, unordered_set<string> > &prevMap, vector<string> &ret, const string &word, vector<vector<string> > &result) {
if (prevMap[word].size() == 0) {
ret.push_back(word);
vector<string> path = ret;
reverse(path.begin(), path.end());
result.push_back(path);
ret.pop_back();
return ;
}
ret.push_back(word);
for (auto it = prevMap[word].begin(); it != prevMap[word].end(); it ++) {
generateResult(prevMap, ret, *it, result);
}
ret.pop_back();
}
// PD_TRACE_DECLARE_FUNCTION ( COORD_CMDSTATBASE_EXE, "_coordCMDStatisticsBase::execute" )
INT32 _coordCMDStatisticsBase::execute( MsgHeader *pMsg,
pmdEDUCB *cb,
INT64 &contextID,
rtnContextBuf *buf )
{
INT32 rc = SDB_OK;
PD_TRACE_ENTRY ( COORD_CMDSTATBASE_EXE ) ;
SDB_RTNCB *pRtncb = pmdGetKRCB()->getRTNCB() ;
contextID = -1 ;
coordQueryOperator queryOpr( isReadOnly() ) ;
rtnContextCoord *pContext = NULL ;
coordQueryConf queryConf ;
coordSendOptions sendOpt ;
queryConf._openEmptyContext = openEmptyContext() ;
CHAR *pHint = NULL ;
rc = msgExtractQuery( (CHAR*)pMsg, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, &pHint );
PD_RC_CHECK ( rc, PDERROR, "Execute failed, failed to parse query "
"request, rc: %d", rc ) ;
try
{
BSONObj boHint( pHint ) ;
BSONElement ele = boHint.getField( FIELD_NAME_COLLECTION ) ;
PD_CHECK ( ele.type() == String,
SDB_INVALIDARG, error, PDERROR,
"Execute failed, failed to get the field(%s)",
FIELD_NAME_COLLECTION ) ;
queryConf._realCLName = ele.str() ;
}
catch( std::exception &e )
{
PD_RC_CHECK ( rc, PDERROR, "Execute failed, occured unexpected "
"error:%s", e.what() ) ;
}
rc = queryOpr.init( _pResource, cb, getTimeout() ) ;
if ( rc )
{
PD_LOG( PDERROR, "Init query operator failed, rc: %d", rc ) ;
goto error ;
}
rc = queryOpr.queryOrDoOnCL( pMsg, cb, &pContext,
sendOpt, &queryConf, buf ) ;
PD_RC_CHECK( rc, PDERROR, "Query failed, rc: %d", rc ) ;
rc = generateResult( pContext, cb ) ;
PD_RC_CHECK( rc, PDERROR, "Failed to execute statistics, rc: %d", rc ) ;
contextID = pContext->contextID() ;
pContext->reopen() ;
done:
PD_TRACE_EXITRC ( COORD_CMDSTATBASE_EXE, rc ) ;
return rc;
error:
if ( pContext )
{
pRtncb->contextDelete( pContext->contextID(), cb ) ;
}
goto done ;
}
