#include<bits/stdc++.h>
#define int long long
#define MOD 998244353
using namespace std;
int n,c,a[1000003],f[1000003],pre[1000003],ans=1,lmt[1000003],gg;
bool chk(int X,int Y){
	if(X>Y)swap(X,Y);
	if(X>1000000)return false;
	if(X==0||Y==0)return true;
	if((c/(X*X))<Y)return false;
	return true;
}
int calc(int X){
	if(X==0)return c;
	if(chk(X,X))return f[X];
	return (int)(sqrt(c/X));
}
int getsum(int l,int r){return ((r-l+1)%MOD)*(((l+r)%MOD)*((MOD+1)/2)%MOD)%MOD;}
int lft,rgt,mid;
int getnum(int X,int Y){
	X=min(X,Y);
	X=min(X,gg);
	int ret=0;
	lft=0;
	rgt=X;
	while(lft<rgt){
		mid=((lft+rgt)>>1)+1;
		if(f[mid]>=Y)lft=mid;
		else rgt=mid=1;
	}
	ret=((Y%MOD)*((lft+1)%MOD)-getsum(-1,lft-1))%MOD;
	ret=(ret+pre[X]-pre[lft])%MOD;
	return ret;
}
signed main(){
	ios::sync_with_stdio(false);
	cin>>n>>c;
	for(int i=1;i<=n;i++)cin>>a[i];
	for(int i=1;i<=n;i++){
		if(a[i]==-1&&((i==1)||(a[i-1]==0)||(a[i-1]==-1))&&((i==n)||(a[i+1]==0)||(a[i+1]==-1))){
			cout<<-1;
			return 0;
		}
	}
	for(int i=1;i<=1000000;i++){
		if(i*i*i>c)f[i]=i-1;
		else f[i]=(c/(i*i));
		if(i*i*i<=c)gg=i;
		pre[i]=(pre[i-1]+f[i]-i+1)%MOD;
	}
	f[0]=c;
	for(int i=1;i<=n;i++)lmt[i]=c;
	for(int i=1;i<n;i++){
		if(a[i]!=-1&&a[i+1]!=-1&&(!chk(a[i],a[i+1]))){
			cout<<0;
			return 0;
		}
	}
	for(int i=1;i<=n;i++){
		if(a[i]!=-1){
			if(i>1)lmt[i-1]=min(lmt[i-1],calc(a[i]));
			if(i<n)lmt[i+1]=min(lmt[i+1],calc(a[i]));
		}
	}
	for(int i=1;i<=n;i++){
		if(a[i]!=-1)continue;
		if(i==n||a[i+1]!=-1){
			ans=ans*((lmt[i]+1)%MOD)%MOD;
			continue;
		}
		ans=ans*((getnum(lmt[i],lmt[i+1])+getnum(lmt[i+1],lmt[i])-min(lmt[i],gg)-1)%MOD)%MOD;
		i++;
	}
	ans%=MOD;
	ans+=MOD;
	ans%=MOD;
	cout<<ans;
	return 0;
}