# Fibonacci:  F(n) = F(n-1) + F(n-2)
nterms = 20

# first two terms
n1 = 0
n2 = 1
count = 2

# check if the number of terms is valid
if(nterms <= 0) {
    print("Plese enter a positive integer")
} else {
    if(nterms == 1) {
        print("Fibonacci sequence:")
        print(n1)
    } else {
        print("Fibonacci sequence:")
        print(n1)
        print(n2)

        while(count < nterms) {
            nth = n1 + n2
            print(nth)
            # update values
            n1 = n2
            n2 = nth
            count = count + 1
        }
    }
}

