记录编号 |
326315 |
评测结果 |
AAAAAAAAAA |
题目名称 |
森林大礼包 |
最终得分 |
100 |
用户昵称 |
Hzoi_Go灬Fire |
是否通过 |
通过 |
代码语言 |
C++ |
运行时间 |
1.108 s |
提交时间 |
2016-10-21 07:20:17 |
内存使用 |
8.15 MiB |
显示代码纯文本
#include<cmath>
#include<cstring>
#include<algorithm>
#include<cstdio>
#include<cstdlib>
#include<iostream>
#define Inf 0x3f3f3f3f
#define LL unsigned long long
#define Begin freopen("three_squirrels.in","r",stdin);freopen("three_squirrels.out","w",stdout);
#define End fclose(stdin);fclose(stdout);
using namespace std;
const int maxn=150000;
const int mod=1e9+7;
struct Edge{
int next,to,dis;
}e[maxn<<2];
int n;
LL hav[maxn],num[maxn];
int head[maxn],len;
bool vis[maxn];
void Insert(int x,int y){
len++;e[len].to=y;e[len].next=head[x];head[x]=len;
}
void Init();
int Dfs(int x){
if(hav[x] && vis[x])return hav[x];
if(x==0)return 1;
for(int i=head[x];i;i=e[i].next){
int j=e[i].to;
hav[x]+=Dfs(j);
hav[x]%=mod;
}
vis[x]=1;
return hav[x];
}
int main(){
Begin;
Init();
//system("pause");
End;
return 0;
}
void Init(){
scanf("%d",&n);hav[0]=1;
for(int i=1;i<=n;i++){
scanf("%d",&num[i]);
for(int j=1;j<=num[i];j++){
int x;scanf("%d",&x);
Insert(i,x);
}
}
printf("%d\n",Dfs(n)%mod);
}
/*
5
2 0 3
2 0 0
3 0 0 0
4 0 0 0 0
5 0 0 1 0 0
*/