andttttttis_nat0ttis_natsxis_natxis_natlistnilttis_natlistconsxxsandis_natxis_natlistxsfromxfromCondis_natlistxxfromCondttconsxxsfromconssxconsxxsand2tt0is_nat100s1is_natlist1nil0cons2from1fromCond2FULLTRS//AProVE_10/challenge_fab.trs