#include <bits/stdc++.h>
#define MOD 998244353

/* 0 = <
   1 = =
   2 = >
*/

typedef long long ll;

int arr[100001];
int memo[100001][201][4];

int n;

int jacobian(int i, int val, int sg)
{
	if(i == n+1)
	return 1;
	if(memo[i][val][sg] != -1)
	return memo[i][val][sg];
	int ans = 0;
	if(arr[i] != -1)
	{
		if(i == 1)
		ans = ((jacobian(i+1, arr[i], 0)%MOD) + (jacobian(i+1, arr[i], 1)%MOD))%MOD;
		else if((i > 1) && (i < n))
		{
			if(((val < arr[i]) && ((sg == 1) || (sg == 2))) || ((val == arr[i]) && ((sg == 0) || (sg == 2))) || ((val > arr[i]) && ((sg == 0) || (sg == 1))))
			ans = 0;
			else
			{
				if(!sg)
				ans = ((jacobian(i+1, arr[i], 0)%MOD) + (jacobian(i+1, arr[i], 1)%MOD))%MOD;
				else if(sg == 1)
				ans = ((((jacobian(i+1, arr[i], 0)%MOD) + (jacobian(i+1, arr[i], 1)%MOD))%MOD) + (jacobian(i+1, arr[i], 2)%MOD))%MOD;
				else ans = ((jacobian(i+1, arr[i], 0)%MOD) + (((jacobian(i+1, arr[i], 1)%MOD) + (jacobian(i+1, arr[i], 2)%MOD))%MOD))%MOD;
			}
		}
		else
		{
			if((((val < arr[i]) && ((sg == 1) || (sg == 2))) || ((val == arr[i]) && ((sg == 0) || (sg == 2))) || ((val > arr[i]) && ((sg == 0) || (sg == 1)))) || (!sg))
			ans = 0;
			else ans = jacobian(i+1, arr[i], 3)%MOD;
		}
	}
	else
	{
		for(int j=1;j<=200;j++)
		{
			if(i == 1)
			ans = ((ans%MOD) + (((jacobian(i+1, j, 0)%MOD) + (jacobian(i+1, j, 1)%MOD))%MOD))%MOD;
			else if((i > 1) && (i < n))
			{
				if(((val < j) && ((sg == 1) || (sg == 2))) || ((val == j) && ((sg == 0) || (sg == 2))) || ((val > j) && ((sg == 0) || (sg == 1))))
				continue;
				else
				{
					if(!sg)
					ans = ((ans%MOD) + (((jacobian(i+1, j, 0)%MOD) + (jacobian(i+1, j, 1)%MOD))%MOD))%MOD;
					else if(sg == 1)
					ans = ((ans%MOD) + (((((jacobian(i+1, j, 0)%MOD) + (jacobian(i+1, j, 1)%MOD))%MOD) + (jacobian(i+1, j, 2)%MOD))%MOD))%MOD;
					else ans = ((ans%MOD) + ((jacobian(i+1, j, 0)%MOD) + (((jacobian(i+1, j, 1)%MOD) + (jacobian(i+1, j, 2)%MOD))%MOD))%MOD)%MOD;
				}
			}
			else
			{
				if((((val < j) && ((sg == 1) || (sg == 2))) || ((val == j) && ((sg == 0) || (sg == 2))) || ((val > j) && ((sg == 0) || (sg == 1)))) || (!sg))
				continue;
				else ans = ((ans%MOD) + (jacobian(i+1, j, 3)%MOD))%MOD;
			}
		}
	}
	memo[i][val][sg] = ans;
	return ans;
}

int main(void)
{
	std::ios_base::sync_with_stdio(false);
	std::cin.tie(NULL);
	std::cout.tie(NULL);
	memset(memo, -1, sizeof(memo));
	std::cin>>n;
	for(int i=1;i<=n;i++)
	std::cin>>arr[i];
	int ans = jacobian(1, 0, 3)%MOD;
	std::cout<<ans<<"\n";
	return 0;
}