这是我改对之后的代码

#include<cstdio>
#include<iostream>
#define ll long long
using namespace std;
const int N=1e5+5,p=1e9+7;
struct D{int q[11];}e[N];
int n,cnt[N];
ll a[N],ans;
ll dfs(int x)
{
	if(a[x]) return a[x];
	for(int i=1;i<=cnt[x];i++)
	{
		a[x]+=dfs(e[x].q[i]);
		a[x]%=p;
	}
	return a[x];
}
int main()
{
//	freopen("three_squirrels8.in","r",stdin);
//	freopen("three_squirrels.out","w",stdout);
	scanf("%d",&n);
	a[0]=1;
	for(int i=1;i<=n;i++)
	{
		scanf("%d",&cnt[i]);
		for(int j=1;j<=cnt[i];j++)
		scanf("%d",&e[i].q[j]);
	}
	printf("%I64d\n",dfs(n));
	return 0;
}

这是我得了70分的代码

#include<cstdio>
#include<iostream>
#define ll long long
using namespace std;
const int N=1e5+5,p=1e9+7;
struct D{int q[11];}e[N];
int n,cnt[N];
ll a[N],ans;
ll dfs(int x)
{
	if(a[x]) return a[x];
	for(int i=1;i<=cnt[x];i++)
	{
		a[x]+=dfs(e[x].q[i]);
		a[x]%=p;
	}
	return a[x];
}
int main()
{
//	freopen("three_squirrels8.in","r",stdin);
//	freopen("three_squirrels.out","w",stdout);
	scanf("%d",&n);
	a[0]=1;
	for(int i=1;i<=n;i++)
	{
		scanf("%d",&cnt[i]);
		for(int j=1;j<=cnt[i];j++)
		scanf("%d",&e[i].q[j]);
	}
	for(int i=1;i<n;i++)
	for(int j=1;j<=cnt[i];j++)
	{
		a[i]+=dfs( e[i].q[j] );
		a[i]%=p;
	}
	for(int i=1;i<=cnt[n];i++)
	{
		ans+=a[ e[n].q[i] ];
		ans%=p;
	}
	printf("%I64d\n",ans);
	return 0;
}

请问大家是哪里出了锅，$qwq$