fond
Model Checking Contest 2023
13th edition, Paris, France, April 26, 2023 (at TOOLympics II)
Execution of r233-tall-167856419000494
Last Updated
May 14, 2023

About the Execution of LTSMin+red for LeafsetExtension-PT-S16C4

Execution Summary
Max Memory
Used (MB)
Time wait (ms) CPU Usage (ms) I/O Wait (ms) Computed Result Execution
Status
2209.659 3576808.00 14274711.00 344.50 FFFTTTTTFTFFTTFT normal

Execution Chart

We display below the execution chart for this examination (boot time has been removed).

Trace from the execution

Formatting '/data/fkordon/mcc2023-input.r233-tall-167856419000494.qcow2', fmt=qcow2 size=4294967296 backing_file=/data/fkordon/mcc2023-input.qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
Waiting for the VM to be ready (probing ssh)
...............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
=====================================================================
Generated by BenchKit 2-5348
Executing tool ltsminxred
Input is LeafsetExtension-PT-S16C4, examination is ReachabilityCardinality
Time confinement is 3600 seconds
Memory confinement is 16384 MBytes
Number of cores is 4
Run identifier is r233-tall-167856419000494
=====================================================================

--------------------
preparation of the directory to be used:
/home/mcc/execution
total 1.4M
-rw-r--r-- 1 mcc users 14K Feb 25 16:52 CTLCardinality.txt
-rw-r--r-- 1 mcc users 96K Feb 25 16:52 CTLCardinality.xml
-rw-r--r-- 1 mcc users 15K Feb 25 16:51 CTLFireability.txt
-rw-r--r-- 1 mcc users 86K Feb 25 16:51 CTLFireability.xml
-rw-r--r-- 1 mcc users 6.5K Feb 25 16:21 LTLCardinality.txt
-rw-r--r-- 1 mcc users 30K Feb 25 16:21 LTLCardinality.xml
-rw-r--r-- 1 mcc users 4.0K Feb 25 16:21 LTLFireability.txt
-rw-r--r-- 1 mcc users 19K Feb 25 16:21 LTLFireability.xml
-rw-r--r-- 1 mcc users 15K Feb 25 16:53 ReachabilityCardinality.txt
-rw-r--r-- 1 mcc users 88K Feb 25 16:53 ReachabilityCardinality.xml
-rw-r--r-- 1 mcc users 16K Feb 25 16:52 ReachabilityFireability.txt
-rw-r--r-- 1 mcc users 73K Feb 25 16:52 ReachabilityFireability.xml
-rw-r--r-- 1 mcc users 2.2K Feb 25 16:21 UpperBounds.txt
-rw-r--r-- 1 mcc users 4.2K Feb 25 16:21 UpperBounds.xml
-rw-r--r-- 1 mcc users 6 Mar 5 18:22 equiv_col
-rw-r--r-- 1 mcc users 6 Mar 5 18:22 instance
-rw-r--r-- 1 mcc users 6 Mar 5 18:22 iscolored
-rw-r--r-- 1 mcc users 905K Mar 5 18:22 model.pnml

--------------------
content from stdout:

=== Data for post analysis generated by BenchKit (invocation template)

The expected result is a vector of booleans
BOOL_VECTOR

here is the order used to build the result vector(from text file)
FORMULA_NAME LeafsetExtension-PT-S16C4-ReachabilityCardinality-00
FORMULA_NAME LeafsetExtension-PT-S16C4-ReachabilityCardinality-01
FORMULA_NAME LeafsetExtension-PT-S16C4-ReachabilityCardinality-02
FORMULA_NAME LeafsetExtension-PT-S16C4-ReachabilityCardinality-03
FORMULA_NAME LeafsetExtension-PT-S16C4-ReachabilityCardinality-04
FORMULA_NAME LeafsetExtension-PT-S16C4-ReachabilityCardinality-05
FORMULA_NAME LeafsetExtension-PT-S16C4-ReachabilityCardinality-06
FORMULA_NAME LeafsetExtension-PT-S16C4-ReachabilityCardinality-07
FORMULA_NAME LeafsetExtension-PT-S16C4-ReachabilityCardinality-08
FORMULA_NAME LeafsetExtension-PT-S16C4-ReachabilityCardinality-09
FORMULA_NAME LeafsetExtension-PT-S16C4-ReachabilityCardinality-10
FORMULA_NAME LeafsetExtension-PT-S16C4-ReachabilityCardinality-11
FORMULA_NAME LeafsetExtension-PT-S16C4-ReachabilityCardinality-12
FORMULA_NAME LeafsetExtension-PT-S16C4-ReachabilityCardinality-13
FORMULA_NAME LeafsetExtension-PT-S16C4-ReachabilityCardinality-14
FORMULA_NAME LeafsetExtension-PT-S16C4-ReachabilityCardinality-15

=== Now, execution of the tool begins

BK_START 1679537423059

bash -c /home/mcc/BenchKit/BenchKit_head.sh 2> STDERR ; echo ; echo -n "BK_STOP " ; date -u +%s%3N
Invoking MCC driver with
BK_TOOL=ltsminxred
BK_EXAMINATION=ReachabilityCardinality
BK_BIN_PATH=/home/mcc/BenchKit/bin/
BK_TIME_CONFINEMENT=3600
BK_INPUT=LeafsetExtension-PT-S16C4
Applying reductions before tool ltsmin
Invoking reducer
Running Version 202303021504
[2023-03-23 02:10:24] [INFO ] Running its-tools with arguments : [-pnfolder, /home/mcc/execution, -examination, ReachabilityCardinality, -timeout, 360, -rebuildPNML]
[2023-03-23 02:10:24] [INFO ] Parsing pnml file : /home/mcc/execution/model.pnml
[2023-03-23 02:10:24] [INFO ] Load time of PNML (sax parser for PT used): 127 ms
[2023-03-23 02:10:24] [INFO ] Transformed 1542 places.
[2023-03-23 02:10:24] [INFO ] Transformed 1449 transitions.
[2023-03-23 02:10:24] [INFO ] Parsed PT model containing 1542 places and 1449 transitions and 4668 arcs in 331 ms.
Parsed 16 properties from file /home/mcc/execution/ReachabilityCardinality.xml in 16 ms.
Working with output stream class java.io.PrintStream
Incomplete random walk after 10000 steps, including 297 resets, run finished after 642 ms. (steps per millisecond=15 ) properties (out of 16) seen :5
FORMULA LeafsetExtension-PT-S16C4-ReachabilityCardinality-15 TRUE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA LeafsetExtension-PT-S16C4-ReachabilityCardinality-14 FALSE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA LeafsetExtension-PT-S16C4-ReachabilityCardinality-11 FALSE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA LeafsetExtension-PT-S16C4-ReachabilityCardinality-07 TRUE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA LeafsetExtension-PT-S16C4-ReachabilityCardinality-04 TRUE TECHNIQUES TOPOLOGICAL RANDOM_WALK
Incomplete Best-First random walk after 10001 steps, including 27 resets, run finished after 42 ms. (steps per millisecond=238 ) properties (out of 11) seen :0
Incomplete Best-First random walk after 10001 steps, including 28 resets, run finished after 45 ms. (steps per millisecond=222 ) properties (out of 11) seen :0
Incomplete Best-First random walk after 10001 steps, including 27 resets, run finished after 35 ms. (steps per millisecond=285 ) properties (out of 11) seen :0
Incomplete Best-First random walk after 10001 steps, including 29 resets, run finished after 34 ms. (steps per millisecond=294 ) properties (out of 11) seen :0
Incomplete Best-First random walk after 10001 steps, including 28 resets, run finished after 31 ms. (steps per millisecond=322 ) properties (out of 11) seen :0
Incomplete Best-First random walk after 10001 steps, including 28 resets, run finished after 22 ms. (steps per millisecond=454 ) properties (out of 11) seen :0
Incomplete Best-First random walk after 10001 steps, including 28 resets, run finished after 42 ms. (steps per millisecond=238 ) properties (out of 11) seen :0
Incomplete Best-First random walk after 10001 steps, including 17 resets, run finished after 27 ms. (steps per millisecond=370 ) properties (out of 11) seen :0
Incomplete Best-First random walk after 10001 steps, including 28 resets, run finished after 31 ms. (steps per millisecond=322 ) properties (out of 11) seen :1
FORMULA LeafsetExtension-PT-S16C4-ReachabilityCardinality-09 TRUE TECHNIQUES TOPOLOGICAL BESTFIRST_WALK
Incomplete Best-First random walk after 10001 steps, including 28 resets, run finished after 34 ms. (steps per millisecond=294 ) properties (out of 10) seen :0
Incomplete Best-First random walk after 10001 steps, including 28 resets, run finished after 31 ms. (steps per millisecond=322 ) properties (out of 10) seen :0
Running SMT prover for 10 properties.
// Phase 1: matrix 1449 rows 1542 cols
[2023-03-23 02:10:26] [INFO ] Computed 93 place invariants in 92 ms
[2023-03-23 02:10:26] [INFO ] [Real]Absence check using 19 positive place invariants in 33 ms returned sat
[2023-03-23 02:10:26] [INFO ] [Real]Absence check using 19 positive and 74 generalized place invariants in 56 ms returned sat
[2023-03-23 02:10:27] [INFO ] After 796ms SMT Verify possible using all constraints in real domain returned unsat :1 sat :0 real:9
[2023-03-23 02:10:27] [INFO ] [Nat]Absence check using 19 positive place invariants in 9 ms returned sat
[2023-03-23 02:10:27] [INFO ] [Nat]Absence check using 19 positive and 74 generalized place invariants in 49 ms returned sat
[2023-03-23 02:10:27] [INFO ] After 478ms SMT Verify possible using all constraints in natural domain returned unsat :10 sat :0
FORMULA LeafsetExtension-PT-S16C4-ReachabilityCardinality-13 TRUE TECHNIQUES STRUCTURAL_REDUCTION TOPOLOGICAL SAT_SMT
FORMULA LeafsetExtension-PT-S16C4-ReachabilityCardinality-12 TRUE TECHNIQUES STRUCTURAL_REDUCTION TOPOLOGICAL SAT_SMT
FORMULA LeafsetExtension-PT-S16C4-ReachabilityCardinality-10 FALSE TECHNIQUES STRUCTURAL_REDUCTION TOPOLOGICAL SAT_SMT
FORMULA LeafsetExtension-PT-S16C4-ReachabilityCardinality-08 FALSE TECHNIQUES STRUCTURAL_REDUCTION TOPOLOGICAL SAT_SMT
FORMULA LeafsetExtension-PT-S16C4-ReachabilityCardinality-06 TRUE TECHNIQUES STRUCTURAL_REDUCTION TOPOLOGICAL SAT_SMT
FORMULA LeafsetExtension-PT-S16C4-ReachabilityCardinality-05 TRUE TECHNIQUES STRUCTURAL_REDUCTION TOPOLOGICAL SAT_SMT
FORMULA LeafsetExtension-PT-S16C4-ReachabilityCardinality-03 TRUE TECHNIQUES STRUCTURAL_REDUCTION TOPOLOGICAL SAT_SMT
FORMULA LeafsetExtension-PT-S16C4-ReachabilityCardinality-02 FALSE TECHNIQUES STRUCTURAL_REDUCTION TOPOLOGICAL SAT_SMT
FORMULA LeafsetExtension-PT-S16C4-ReachabilityCardinality-01 FALSE TECHNIQUES STRUCTURAL_REDUCTION TOPOLOGICAL SAT_SMT
FORMULA LeafsetExtension-PT-S16C4-ReachabilityCardinality-00 FALSE TECHNIQUES STRUCTURAL_REDUCTION TOPOLOGICAL SAT_SMT
Fused 10 Parikh solutions to 0 different solutions.
Parikh walk visited 0 properties in 1 ms.
All properties solved without resorting to model-checking.
Total runtime 2908 ms.
pnml2lts-sym model.pnml --lace-workers=4 --vset=lddmc --saturation=sat -rbs,w2W,ru,hf --sylvan-sizes=20,28,20,28 --invariant=/tmp/453/inv_0_ --invariant=/tmp/453/inv_1_ --invariant=/tmp/453/inv_2_ --invariant=/tmp/453/inv_3_ --invariant=/tmp/453/inv_4_ --invariant=/tmp/453/inv_5_ --invariant=/tmp/453/inv_6_ --invariant=/tmp/453/inv_7_ --invariant=/tmp/453/inv_8_ --invariant=/tmp/453/inv_9_ --invariant=/tmp/453/inv_10_ --invariant=/tmp/453/inv_11_ --invariant=/tmp/453/inv_12_ --invariant=/tmp/453/inv_13_ --invariant=/tmp/453/inv_14_ --invariant=/tmp/453/inv_15_ --inv-par
TIME LIMIT: Killed by timeout after 3570 seconds
MemTotal: 16393216 kB
MemFree: 13939876 kB
After kill :
MemTotal: 16393216 kB
MemFree: 16100856 kB
Could not compute solution for formula : LeafsetExtension-PT-S16C4-ReachabilityCardinality-00
Could not compute solution for formula : LeafsetExtension-PT-S16C4-ReachabilityCardinality-01
Could not compute solution for formula : LeafsetExtension-PT-S16C4-ReachabilityCardinality-02
Could not compute solution for formula : LeafsetExtension-PT-S16C4-ReachabilityCardinality-03
Could not compute solution for formula : LeafsetExtension-PT-S16C4-ReachabilityCardinality-04
Could not compute solution for formula : LeafsetExtension-PT-S16C4-ReachabilityCardinality-05
Could not compute solution for formula : LeafsetExtension-PT-S16C4-ReachabilityCardinality-06
Could not compute solution for formula : LeafsetExtension-PT-S16C4-ReachabilityCardinality-07
Could not compute solution for formula : LeafsetExtension-PT-S16C4-ReachabilityCardinality-08
Could not compute solution for formula : LeafsetExtension-PT-S16C4-ReachabilityCardinality-09
Could not compute solution for formula : LeafsetExtension-PT-S16C4-ReachabilityCardinality-10
Could not compute solution for formula : LeafsetExtension-PT-S16C4-ReachabilityCardinality-11
Could not compute solution for formula : LeafsetExtension-PT-S16C4-ReachabilityCardinality-12
Could not compute solution for formula : LeafsetExtension-PT-S16C4-ReachabilityCardinality-13
Could not compute solution for formula : LeafsetExtension-PT-S16C4-ReachabilityCardinality-14
Could not compute solution for formula : LeafsetExtension-PT-S16C4-ReachabilityCardinality-15

BK_STOP 1679540999867

--------------------
content from stderr:

+ ulimit -s 65536
+ [[ -z '' ]]
+ export LTSMIN_MEM_SIZE=8589934592
+ LTSMIN_MEM_SIZE=8589934592
+ export PYTHONPATH=/home/mcc/BenchKit/itstools/pylibs
+ PYTHONPATH=/home/mcc/BenchKit/itstools/pylibs
+ export LD_LIBRARY_PATH=/home/mcc/BenchKit/itstools/pylibs:
+ LD_LIBRARY_PATH=/home/mcc/BenchKit/itstools/pylibs:
++ sed s/.jar//
++ perl -pe 's/.*\.//g'
++ ls /home/mcc/BenchKit/bin//../reducer/bin//../../itstools//itstools/plugins/fr.lip6.move.gal.application.pnmcc_1.0.0.202303021504.jar
+ VERSION=202303021504
+ echo 'Running Version 202303021504'
+ /home/mcc/BenchKit/bin//../reducer/bin//../../itstools//itstools/its-tools -pnfolder /home/mcc/execution -examination ReachabilityCardinality -timeout 360 -rebuildPNML
mcc2023
rfs formula name LeafsetExtension-PT-S16C4-ReachabilityCardinality-00
rfs formula type EF
rfs formula formula --invariant=/tmp/453/inv_0_
rfs formula name LeafsetExtension-PT-S16C4-ReachabilityCardinality-01
rfs formula type EF
rfs formula formula --invariant=/tmp/453/inv_1_
rfs formula name LeafsetExtension-PT-S16C4-ReachabilityCardinality-02
rfs formula type EF
rfs formula formula --invariant=/tmp/453/inv_2_
rfs formula name LeafsetExtension-PT-S16C4-ReachabilityCardinality-03
rfs formula type AG
rfs formula formula --invariant=/tmp/453/inv_3_
rfs formula name LeafsetExtension-PT-S16C4-ReachabilityCardinality-04
rfs formula type EF
rfs formula formula --invariant=/tmp/453/inv_4_
rfs formula name LeafsetExtension-PT-S16C4-ReachabilityCardinality-05
rfs formula type AG
rfs formula formula --invariant=/tmp/453/inv_5_
rfs formula name LeafsetExtension-PT-S16C4-ReachabilityCardinality-06
rfs formula type AG
rfs formula formula --invariant=/tmp/453/inv_6_
rfs formula name LeafsetExtension-PT-S16C4-ReachabilityCardinality-07
rfs formula type EF
rfs formula formula --invariant=/tmp/453/inv_7_
rfs formula name LeafsetExtension-PT-S16C4-ReachabilityCardinality-08
rfs formula type EF
rfs formula formula --invariant=/tmp/453/inv_8_
rfs formula name LeafsetExtension-PT-S16C4-ReachabilityCardinality-09
rfs formula type EF
rfs formula formula --invariant=/tmp/453/inv_9_
rfs formula name LeafsetExtension-PT-S16C4-ReachabilityCardinality-10
rfs formula type EF
rfs formula formula --invariant=/tmp/453/inv_10_
rfs formula name LeafsetExtension-PT-S16C4-ReachabilityCardinality-11
rfs formula type AG
rfs formula formula --invariant=/tmp/453/inv_11_
rfs formula name LeafsetExtension-PT-S16C4-ReachabilityCardinality-12
rfs formula type AG
rfs formula formula --invariant=/tmp/453/inv_12_
rfs formula name LeafsetExtension-PT-S16C4-ReachabilityCardinality-13
rfs formula type AG
rfs formula formula --invariant=/tmp/453/inv_13_
rfs formula name LeafsetExtension-PT-S16C4-ReachabilityCardinality-14
rfs formula type AG
rfs formula formula --invariant=/tmp/453/inv_14_
rfs formula name LeafsetExtension-PT-S16C4-ReachabilityCardinality-15
rfs formula type EF
rfs formula formula --invariant=/tmp/453/inv_15_
pnml2lts-sym: Exploration order is bfs-prev
pnml2lts-sym: Saturation strategy is sat
pnml2lts-sym: Guided search strategy is unguided
pnml2lts-sym: Attractor strategy is default
pnml2lts-sym: opening model.pnml
pnml2lts-sym: Edge label is id
Warning: program compiled against libxml 210 using older 209
pnml2lts-sym: Petri net has 1542 places, 1449 transitions and 4668 arcs
pnml2lts-sym: Petri net gen analyzed
pnml2lts-sym: There are no safe places
pnml2lts-sym: Loading Petri net took 0.010 real 0.020 user 0.000 sys
pnml2lts-sym: Initializing regrouping layer
pnml2lts-sym: Regroup specification: bs,w2W,ru,hf
pnml2lts-sym: Regroup Boost's Sloan
pnml2lts-sym: Regroup over-approximate must-write to may-write
pnml2lts-sym: Regroup Row sUbsume
pnml2lts-sym: Reqroup Horizontal Flip
pnml2lts-sym: Regrouping: 1449->1449 groups
pnml2lts-sym: Regrouping took 1.280 real 1.280 user 0.000 sys
pnml2lts-sym: state vector length is 1542; there are 1449 groups
pnml2lts-sym: Creating a multi-core ListDD domain.
pnml2lts-sym: Sylvan allocates 15.000 GB virtual memory for nodes table and operation cache.
pnml2lts-sym: Initial nodes table and operation cache requires 60.00 MB.
pnml2lts-sym: Using GBgetTransitionsShortR2W as next-state function
pnml2lts-sym: vset_sylvan: starting garbage collection
pnml2lts-sym: vset_sylvan: garbage collection done
pnml2lts-sym: got initial state
pnml2lts-sym: vset_sylvan: starting garbage collection
pnml2lts-sym: vset_sylvan: garbage collection done
pnml2lts-sym: vset_sylvan: starting garbage collection
pnml2lts-sym: vset_sylvan: garbage collection done
Killing (15) : 459
Killing (9) : 459

Sequence of Actions to be Executed by the VM

This is useful if one wants to reexecute the tool in the VM from the submitted image disk.

set -x
# this is for BenchKit: configuration of major elements for the test
export BK_INPUT="LeafsetExtension-PT-S16C4"
export BK_EXAMINATION="ReachabilityCardinality"
export BK_TOOL="ltsminxred"
export BK_RESULT_DIR="/tmp/BK_RESULTS/OUTPUTS"
export BK_TIME_CONFINEMENT="3600"
export BK_MEMORY_CONFINEMENT="16384"
export BK_BIN_PATH="/home/mcc/BenchKit/bin/"

# this is specific to your benchmark or test

export BIN_DIR="$HOME/BenchKit/bin"

# remove the execution directoty if it exists (to avoid increse of .vmdk images)
if [ -d execution ] ; then
rm -rf execution
fi

# this is for BenchKit: explicit launching of the test
echo "====================================================================="
echo " Generated by BenchKit 2-5348"
echo " Executing tool ltsminxred"
echo " Input is LeafsetExtension-PT-S16C4, examination is ReachabilityCardinality"
echo " Time confinement is $BK_TIME_CONFINEMENT seconds"
echo " Memory confinement is 16384 MBytes"
echo " Number of cores is 4"
echo " Run identifier is r233-tall-167856419000494"
echo "====================================================================="
echo
echo "--------------------"
echo "preparation of the directory to be used:"

tar xzf /home/mcc/BenchKit/INPUTS/LeafsetExtension-PT-S16C4.tgz
mv LeafsetExtension-PT-S16C4 execution
cd execution
if [ "ReachabilityCardinality" = "ReachabilityDeadlock" ] || [ "ReachabilityCardinality" = "UpperBounds" ] || [ "ReachabilityCardinality" = "QuasiLiveness" ] || [ "ReachabilityCardinality" = "StableMarking" ] || [ "ReachabilityCardinality" = "Liveness" ] || [ "ReachabilityCardinality" = "OneSafe" ] || [ "ReachabilityCardinality" = "StateSpace" ]; then
rm -f GenericPropertiesVerdict.xml
fi
pwd
ls -lh

echo
echo "--------------------"
echo "content from stdout:"
echo
echo "=== Data for post analysis generated by BenchKit (invocation template)"
echo
if [ "ReachabilityCardinality" = "UpperBounds" ] ; then
echo "The expected result is a vector of positive values"
echo NUM_VECTOR
elif [ "ReachabilityCardinality" != "StateSpace" ] ; then
echo "The expected result is a vector of booleans"
echo BOOL_VECTOR
else
echo "no data necessary for post analysis"
fi
echo
if [ -f "ReachabilityCardinality.txt" ] ; then
echo "here is the order used to build the result vector(from text file)"
for x in $(grep Property ReachabilityCardinality.txt | cut -d ' ' -f 2 | sort -u) ; do
echo "FORMULA_NAME $x"
done
elif [ -f "ReachabilityCardinality.xml" ] ; then # for cunf (txt files deleted;-)
echo echo "here is the order used to build the result vector(from xml file)"
for x in $(grep '' ReachabilityCardinality.xml | cut -d '>' -f 2 | cut -d '<' -f 1 | sort -u) ; do
echo "FORMULA_NAME $x"
done
elif [ "ReachabilityCardinality" = "ReachabilityDeadlock" ] || [ "ReachabilityCardinality" = "QuasiLiveness" ] || [ "ReachabilityCardinality" = "StableMarking" ] || [ "ReachabilityCardinality" = "Liveness" ] || [ "ReachabilityCardinality" = "OneSafe" ] ; then
echo "FORMULA_NAME ReachabilityCardinality"
fi
echo
echo "=== Now, execution of the tool begins"
echo
echo -n "BK_START "
date -u +%s%3N
echo
timeout -s 9 $BK_TIME_CONFINEMENT bash -c "/home/mcc/BenchKit/BenchKit_head.sh 2> STDERR ; echo ; echo -n \"BK_STOP \" ; date -u +%s%3N"
if [ $? -eq 137 ] ; then
echo
echo "BK_TIME_CONFINEMENT_REACHED"
fi
echo
echo "--------------------"
echo "content from stderr:"
echo
cat STDERR ;