SPOJ.com - Problem BAT2

https://www.spoj.com/problems/BAT2/
I am getting NZEC error in the following python sollution although the sample test case passes.do anyone provide some sample test cases to know where the code is giving nzec.thankyou

def solve(pos,inc,dec):

	if pos>=n-1:
		return 0
	if dp[pos][inc][dec] !=-1:
		return dp[pos][inc][dec]
	
	
	dp[pos][inc][dec]=max(solve(pos+1,pos,dec)+1,solve(pos+1,inc,pos)+1,solve(pos+1,inc,dec))
	return dp[pos][inc][dec]

for _ in range(int(input())):
	n=int(input())
	arr=list(map(int,input().split()))
	dp=[[[-1 for i in range(n+1)]for k in range(n+1)]for j in range(n+1)]
	zz=solve(0,0,0)
	print(zz)