Submission #2203977
Source Code Expand
#include <bits/stdc++.h>
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define rep1(i,n) for(int i=1;i<=(int)(n);i++)
#define all(c) c.begin(),c.end()
#define pb push_back
#define fs first
#define sc second
#define show(x) cout << #x << " = " << x << endl
#define chmin(x,y) x=min(x,y)
#define chmax(x,y) x=max(x,y)
using namespace std;
template<class S,class T> ostream& operator<<(ostream& o,const pair<S,T> &p){return o<<"("<<p.fs<<","<<p.sc<<")";}
template<class T> ostream& operator<<(ostream& o,const vector<T> &vc){o<<"sz = "<<vc.size()<<endl<<"[";for(const T& v:vc) o<<v<<",";o<<"]";return o;}
template<unsigned int mod_>
struct ModInt{
using uint = unsigned int;
using ll = long long;
using ull = unsigned long long;
constexpr static uint mod = mod_;
uint v;
ModInt():v(0){}
ModInt(ll v):v(normS(v%mod+mod)){}
explicit operator bool() const {return v!=0;}
static uint normS(const uint &x){return (x<mod)?x:x-mod;} // [0 , 2*mod-1] -> [0 , mod-1]
static ModInt make(const uint &x){ModInt m; m.v=x; return m;}
ModInt operator+(const ModInt& b) const { return make(normS(v+b.v));}
ModInt operator-(const ModInt& b) const { return make(normS(v+mod-b.v));}
ModInt operator-() const { return make(normS(mod-v)); }
ModInt operator*(const ModInt& b) const { return make((ull)v*b.v%mod);}
ModInt operator/(const ModInt& b) const { return *this*b.inv();}
ModInt& operator+=(const ModInt& b){ return *this=*this+b;}
ModInt& operator-=(const ModInt& b){ return *this=*this-b;}
ModInt& operator*=(const ModInt& b){ return *this=*this*b;}
ModInt& operator/=(const ModInt& b){ return *this=*this/b;}
ll extgcd(ll a,ll b,ll &x,ll &y) const{
ll u[]={a,1,0},v[]={b,0,1};
while(*v){
ll t=*u/ *v;
rep(i,3) swap(u[i]-=t*v[i],v[i]);
}
if(u[0]<0) rep(i,3) u[i]=-u[i];
x=u[1],y=u[2];
return u[0];
}
ModInt inv() const{
ll x,y;
extgcd(v,mod,x,y);
return make(normS(x+mod));
}
bool operator==(const ModInt& b) const { return v==b.v;}
bool operator!=(const ModInt& b) const { return v!=b.v;}
friend istream& operator>>(istream &o,ModInt& x){
ll tmp;
o>>tmp;
x=ModInt(tmp);
return o;
}
friend ostream& operator<<(ostream &o,const ModInt& x){ return o<<x.v;}
};
using mint = ModInt<1000000007>;
int N;
vector<vector<int>> G;
using T = array<mint,3>; //0,1,geq 2
vector<deque<T>> dp;
vector<int> depth;
void dfs(int v){
if(G[v].empty()){
dp[v] = {{1,1,0}};
return;
}
for(int u:G[v]){
depth[u] = depth[v] + 1;
dfs(u);
}
int max_len = 0, U = -1;
for(int u:G[v]){
if(dp[u].size() > max_len){
max_len = dp[u].size();
U = u;
}
}
swap(dp[v],dp[U]);
for(int u:G[v]) if(u!=U){
rep(k,dp[u].size()){
T t = {};
rep(i,3) rep(j,2){
t[min(2,i+j)] += dp[v][k][i]*dp[u][k][j];
}
dp[v][k] = t;
}
}
rep(k,dp[v].size()) dp[v][k][0] += dp[v][k][2], dp[v][k][2] = 0;
dp[v].push_front({1,1,0});
}
mint p2[200010];
int main(){
p2[0] = 1;
rep(i,200009) p2[i+1] = p2[i]*2;
cin>>N;
N++;
G.resize(N);
dp.resize(N);
depth.resize(N);
rep1(i,N-1){
int p;
cin>>p;
G[p].pb(i);
}
dfs(0);
vector<int> cnt(N);
rep(i,N) cnt[depth[i]]++;
mint ans = 0;
rep(k,dp[0].size()){
ans += dp[0][k][1] * p2[N-cnt[k]];
}
cout<<ans<<endl;
}
Submission Info
Submission Time |
|
Task |
E - Smuggling Marbles |
User |
sigma425 |
Language |
C++14 (GCC 5.4.1) |
Score |
400 |
Code Size |
3330 Byte |
Status |
TLE |
Exec Time |
3166 ms |
Memory |
239348 KB |
Judge Result
Set Name |
Sample |
Subtask1 |
All |
Score / Max Score |
0 / 0 |
400 / 400 |
0 / 600 |
Status |
|
|
|
Set Name |
Test Cases |
Sample |
00_example_01.txt, 00_example_02.txt, 00_example_03.txt |
Subtask1 |
00_example_01.txt, 00_example_02.txt, 00_example_03.txt, s1_01.txt, s1_02.txt, s1_03.txt, s1_04.txt, s1_05.txt, s1_06.txt, s1_07.txt, s1_08.txt, s1_09.txt, s1_10.txt, s1_11.txt, s1_12.txt, s1_13.txt, s1_14.txt, s1_15.txt, s1_16.txt, s1_17.txt |
All |
00_example_01.txt, 00_example_02.txt, 00_example_03.txt, s1_01.txt, s1_02.txt, s1_03.txt, s1_04.txt, s1_05.txt, s1_06.txt, s1_07.txt, s1_08.txt, s1_09.txt, s1_10.txt, s1_11.txt, s1_12.txt, s1_13.txt, s1_14.txt, s1_15.txt, s1_16.txt, s1_17.txt, s2_01.txt, s2_02.txt, s2_03.txt, s2_04.txt, s2_05.txt, s2_06.txt, s2_07.txt, s2_08.txt, s2_09.txt, s2_10.txt, s2_11.txt, s2_12.txt, s2_13.txt, s2_14.txt, s2_15.txt, s2_16.txt, s2_17.txt, s2_18.txt, s2_19.txt, s2_20.txt, s2_21.txt, s2_22.txt, s2_23.txt, s2_24.txt, s2_25.txt, s2_26.txt, s2_27.txt, s2_28.txt, s2_29.txt, s2_30.txt, s2_31.txt, s2_32.txt |
Case Name |
Status |
Exec Time |
Memory |
00_example_01.txt |
AC |
2 ms |
1024 KB |
00_example_02.txt |
AC |
2 ms |
1024 KB |
00_example_03.txt |
AC |
2 ms |
1024 KB |
s1_01.txt |
AC |
3 ms |
1664 KB |
s1_02.txt |
AC |
3 ms |
1536 KB |
s1_03.txt |
AC |
3 ms |
2304 KB |
s1_04.txt |
AC |
2 ms |
1152 KB |
s1_05.txt |
AC |
3 ms |
1408 KB |
s1_06.txt |
AC |
4 ms |
3456 KB |
s1_07.txt |
AC |
3 ms |
1664 KB |
s1_08.txt |
AC |
16 ms |
2944 KB |
s1_09.txt |
AC |
3 ms |
1536 KB |
s1_10.txt |
AC |
4 ms |
2944 KB |
s1_11.txt |
AC |
3 ms |
1536 KB |
s1_12.txt |
AC |
3 ms |
2176 KB |
s1_13.txt |
AC |
2 ms |
1152 KB |
s1_14.txt |
AC |
4 ms |
2944 KB |
s1_15.txt |
AC |
4 ms |
2816 KB |
s1_16.txt |
AC |
4 ms |
3072 KB |
s1_17.txt |
AC |
4 ms |
2944 KB |
s2_01.txt |
AC |
20 ms |
17024 KB |
s2_02.txt |
AC |
5 ms |
3968 KB |
s2_03.txt |
AC |
182 ms |
132992 KB |
s2_04.txt |
AC |
103 ms |
74496 KB |
s2_05.txt |
AC |
182 ms |
120960 KB |
s2_06.txt |
AC |
278 ms |
192256 KB |
s2_07.txt |
AC |
158 ms |
109184 KB |
s2_08.txt |
AC |
70 ms |
51584 KB |
s2_09.txt |
AC |
272 ms |
188288 KB |
s2_10.txt |
AC |
199 ms |
132992 KB |
s2_11.txt |
AC |
222 ms |
239348 KB |
s2_12.txt |
AC |
5 ms |
4864 KB |
s2_13.txt |
TLE |
3166 ms |
194432 KB |
s2_14.txt |
TLE |
3166 ms |
194304 KB |
s2_15.txt |
TLE |
3164 ms |
176640 KB |
s2_16.txt |
AC |
18 ms |
17024 KB |
s2_17.txt |
AC |
5 ms |
4096 KB |
s2_18.txt |
AC |
146 ms |
123136 KB |
s2_19.txt |
AC |
85 ms |
74368 KB |
s2_20.txt |
AC |
287 ms |
191744 KB |
s2_21.txt |
AC |
290 ms |
183296 KB |
s2_22.txt |
AC |
301 ms |
206976 KB |
s2_23.txt |
AC |
304 ms |
191744 KB |
s2_24.txt |
AC |
220 ms |
160768 KB |
s2_25.txt |
AC |
292 ms |
149632 KB |
s2_26.txt |
AC |
1107 ms |
150400 KB |
s2_27.txt |
TLE |
3165 ms |
176128 KB |
s2_28.txt |
TLE |
3164 ms |
175232 KB |
s2_29.txt |
TLE |
3165 ms |
195712 KB |
s2_30.txt |
TLE |
3165 ms |
195712 KB |
s2_31.txt |
TLE |
3164 ms |
167936 KB |
s2_32.txt |
TLE |
3165 ms |
169728 KB |