YES
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<?xml-stylesheet type="text/xsl" href="cpfHTML.xsl"?>
<certificationProblem xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="cpf.xsd"><input><trsInput><trs><rules><rule><lhs><funapp><name>f</name><arg><var>x</var></arg></funapp></lhs><rhs><var>x</var></rhs></rule><rule><lhs><funapp><name>f</name><arg><var>x</var></arg></funapp></lhs><rhs><funapp><name>f</name><arg><funapp><name>f</name><arg><var>x</var></arg></funapp></arg></funapp></rhs></rule></rules></trs></trsInput></input><cpfVersion>2.1</cpfVersion><proof><crProof><compositionalPcps><trsC><rules><rule><lhs><funapp><name>f</name><arg><var>x</var></arg></funapp></lhs><rhs><var>x</var></rhs></rule></rules></trsC><trsP><rules /></trsP><joinSequences><critPairInfo><left><funapp><name>f</name><arg><funapp><name>f</name><arg><var>y1</var></arg></funapp></arg></funapp></left><peak><funapp><name>f</name><arg><var>y1</var></arg></funapp></peak><right><var>y1</var></right><overlapPositions><positionInTerm /></overlapPositions><intermediateTerms><funapp><name>f</name><arg><var>y1</var></arg></funapp></intermediateTerms></critPairInfo><critPairInfo><left><var>y1</var></left><peak><funapp><name>f</name><arg><var>y1</var></arg></funapp></peak><right><funapp><name>f</name><arg><funapp><name>f</name><arg><var>y1</var></arg></funapp></arg></funapp></right><overlapPositions><positionInTerm /></overlapPositions><intermediateTerms><funapp><name>f</name><arg><var>y1</var></arg></funapp></intermediateTerms></critPairInfo></joinSequences><joinSequences><critPairInfo><left><funapp><name>f</name><arg><funapp><name>f</name><arg><var>y1</var></arg></funapp></arg></funapp></left><peak><funapp><name>f</name><arg><var>y1</var></arg></funapp></peak><right><var>y1</var></right><overlapPositions><positionInTerm /></overlapPositions><intermediateTerms><funapp><name>f</name><arg><var>y1</var></arg></funapp></intermediateTerms></critPairInfo><critPairInfo><left><var>y1</var></left><peak><funapp><name>f</name><arg><var>y1</var></arg></funapp></peak><right><funapp><name>f</name><arg><funapp><name>f</name><arg><var>y1</var></arg></funapp></arg></funapp></right><overlapPositions><positionInTerm /></overlapPositions><intermediateTerms><funapp><name>f</name><arg><var>y1</var></arg></funapp></intermediateTerms></critPairInfo></joinSequences><relativeTerminationProof><rIsEmpty /></relativeTerminationProof><crProof><compositionalPcps><trsC><rules /></trsC><trsP><rules /></trsP><joinSequences /><joinSequences /><relativeTerminationProof><rIsEmpty /></relativeTerminationProof><crProof><orthogonal /></crProof></compositionalPcps></crProof></compositionalPcps></crProof></proof><origin><proofOrigin><tool><name>Hakusan</name><version>0.10</version></tool></proofOrigin></origin></certificationProblem>