câu 2 :
n = int(input("Nhap vao so luong phan tu: "))
print("Nhap vao phan tu cho mang:")
a = []
for i in range(0, n):
  print("\tPhan tu thu", (i+1), "la:", end=" ")
  a.append(int(input()))
  print("Mang vua nhap la:")
for i in range(len(a)):
  print(a[i], end="\\t")
  s_chan = 0
for i in a:
  if (i%2) == 0:
  s_chan += i
  print("Tong cac phan tu chan la:", s_chan)