N=int(input())
A=list(map(int,input().split()))
X=[0,-1,0,1]
L=len(X)-1
for n in range(N,L-1,-1):
  k=A[n]//X[L]
  if k>0:
    for j in range(L,-1,-1):
      A[n-L+j]-=k*X[j]
T=-1
for m in range(N,-1,-1):
  if A[m]!=0:
    T=m
    break
if T==-1: print("0\n0")
else:
  print(T)
  print(' '.join(map(str,A[:m+1])))