c This program has two "end" statements. It will not compile.
c To fix it, change the first "end" to "stop".
program root
real x
print *, "What is your number ?"
read *, x
if (x .lt. 0) then
print *, "Your number has no square root. Bye."
end
end if
print *, "The square root of your number is : ", sqrt(x)
print *, "Bye"
end