lt0sxtrueltx0falseltsxsyltxylogarithmxifalt0xxifatruexhelpx1ifafalsexlogZeroErrorhelpxyifbltyxxyifbtruexyhelphalfxsyifbfalsexyyhalf00halfs00halfssxshalfxltsxsyltxylogarithmxlt0xlogarithmxifalt0xxifatruexhelpx1helpxyltyxhelpxyifbltyxxyifbtruexyhalfxifbtruexyhelphalfxsyhalfssxhalfxtruelogarithmxlt0xfalselogarithmxifalt0xxfalseifatruexhelpx1falseifbtruexyhelphalfxsyhelpxyifbltyxxytruehelpxyltyxfalseltsxsyltxytruelt22ifbtruexyhalfxfalsehalfssxhalfxtruehalf11