Now xwx become a Junior.With great ideals, he want to become a master.So he get hands to prepare Graduate entrance examination.He wants to prepare for advanced mathematics.But he is from CDUTCM.So his advanced mathematics is very poor. In the chapter of integration, he was completely unable to learn.He has a graceful school brother zzk.He said intergration is so easy.In his cognition, the integral is the area surrounded by a straight line and x coordinate axis.May be it is wrong.And zzk's programming is very well.He wants to show up his talent and tell xwx answers by programming.If you are him, please write the answer.

The a,b,c from ax+by+c=0 and Integral interval x1,x2.

a,b,c,x1,x2 are integers

Multiple data read in

The answer of the question.and save 2 decimal place.