#include<bits/stdc++.h>
using namespace std;
const int N=1025,mod=998244353;
int f[N][N],g[N][N],n,tp[N],a[N],b[N],c[N],d[N];
bool vis[N][N];
void getf(int x,int v)
{
	// cout<<x<<" "<<v<<endl;
	if(f[x][v]!=-1)return ;
	if(vis[x][v]){printf("-1\n");exit(0);}
	vis[x][v]=1;
	// cout<<tp[x]<<" ??? "<<c[x]<<endl;
	if(tp[x]==1 && c[x]==v)return f[x][v]=d[x],g[x][v]=1,void();
	getf(b[x],a[x]);
	// cout<<x<<endl;
	int y=f[b[x]][a[x]],num=g[b[x]][a[x]];
	g[x][v]=(num+1)%mod;
	getf(y,v);
	f[x][v]=f[y][v],g[x][v]=(g[x][v]+g[y][v])%mod;
	// cout<<x<<" "<<v<<" "<<f[x][v]<<" "<<g[x][v]<<endl;
	vis[x][v]=0;
}
bool vs[N];
int main()
{
	// freopen(".in.txt","r",stdin);
	scanf("%d",&n);
	for(int i=1;i<=n;i++)
	{
		string s;
		cin>>s;
		if(s=="HALT;")
		{
			tp[i]=2;
			cin>>s;
			scanf("%d",&a[i]);
			cin>>s;
			scanf("%d",&b[i]);
		}
		else
		{
			tp[i]=1;
			scanf("%d",&c[i]);
			cin>>s;
			scanf("%d",&d[i]);
			cin>>s;
			cin>>s;
			scanf("%d",&a[i]);
			cin>>s;
			scanf("%d",&b[i]);
		}
	}
	memset(f,-1,sizeof(f));
	int np=1,ans=1;
	while(1)
	{
		if(tp[np]==2){printf("%d\n",ans);return 0;}
		if(vs[np]){printf("-1\n");return 0;}
		vs[np]=1;
		getf(b[np],a[np]);
		ans=(ans+g[b[np]][a[np]]+1)%mod;
		np=f[b[np]][a[np]];
	}
	return 0;
}