andtrueXXandfalseYfalseiftrueXYXiffalseXYYadd0XXaddsXYsaddXYfirst0XnilfirstsXconsYZconsYfirstXZfromXconsXfromsX2.1addsXYaddXYfirstsXconsYZfirstXZfromXfromsXtruefromXfromsXfromXfromXfromsXfromsXXsX
AProVE
30c4685dac1f9efc56544a9a1f70f53689c698fa rene 20120209 unpublished dirty
http://aprove.informatik.rwth-aachen.de/
John
Doe