program price_calculation
integer,dimension(10)::price
real::average
integer::i,maximum,minimum
open(unit=1,file="prices.txt",status="old", action="read")

do i=1,10
   read(unit=1,fmt=*)price(i)
end do

average=(sum(price(1:10)))/10

open(unit=2,file="mean_prices.txt",status="new", action="write")
write(unit=2,fmt=*)average

maximum=price(1)
minimum=price(1)

do i=1,10
maximum=max(maximum,price(i))
end do

do i=1,10
minimum=min(minimum,price(i))
end do

print*,"Maximum value=",maximum
print*,"Minimum value=",minimum
end program price_calculation