import numpy as np

N=int(eval(input()))

def gcd(a,b):

    c=int(np.floor(a/b))

    return a-b*c

if gcd(N,2)==0:

    print(N)

else:

    print((2*N))
N=int(eval(input()))

if N%2==0:

    print(N)

else:

    print((2*N))
import numpy as np

N = int(eval(input()))


def gcd(a, b):
    c = int(np.floor(a / b))
    return a - b * c


if gcd(N, 2) == 0:
    print(N)
else:
    print((2 * N))

N = int(eval(input()))
if N % 2 == 0:
    print(N)
else:
    print((2 * N))

-import numpy as np - - - -def gcd(a, b): -    c = int(np.floor(a / b)) -    return a - b * c - - -if gcd(N, 2) == 0: +if N % 2 == 0: