return copy to original version #1533

Job	Run time
macos-latest: clang++ Release Threads	23m 48s
macos-latest: clang++ Release OneTBB	3m 11s
macos-latest: clang++ Release PaRSEC	3m 22s
ubuntu-20.04: /usr/bin/g++-9 Release Threads	30m 41s
ubuntu-20.04: /usr/bin/g++-9 Release OneTBB	2m 8s
ubuntu-20.04: /usr/bin/g++-9 Release PaRSEC	2m 25s
macos-latest: clang++ Debug Threads	12m 29s
macos-latest: clang++ Debug OneTBB	2m 3s
macos-latest: clang++ Debug PaRSEC	2m 56s
ubuntu-20.04: /usr/bin/g++-9 Debug Threads	33m 25s
ubuntu-20.04: /usr/bin/g++-9 Debug OneTBB	1m 33s
ubuntu-20.04: /usr/bin/g++-9 Debug PaRSEC	1m 44s
	1h 59m 45s

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