#iterative

def sum_it(n):
    sum=0
    for i in range(1,n+1 ):
        sum += i
    return sum

print (sum_it(100))

#recursive

def sum_rec(n):
    if n == 1:
        return 1
    else:
        return n + sum_rec(n-1)

print (sum_rec(100))
