How do you check a prime number in qbasic?

Answer 1

Cls

input "enter the no. You want to check", a

if a <=0 then print "only natural nos allowed"

if a <=0 end

let m = a - 1

for i = m to 2 step -1

if a mod i = 0 then print "not prime"

if a mod i = 0 then end

next i

print "prime"

end