program main
real::x_1,x_2,x_3,x_4,x_5
read*,x_1,x_2,x_3,x_4,x_5
if(x_1==0)then
 print*,"1"
end if
if(x_2==0)then
 print*,"2"
end if
if(x_3==0)then
 print*,"3"
end if
if(x_4==0)then
 print*,"4"
end if
if(x_5==0)then
 print*,"5"
end if
end program main