結果
| 問題 | No.778 クリスマスツリー |
| ユーザー |
 smiken_61
|
| 提出日時 | 2019-01-03 21:55:11 |
| 言語 | C++11 (gcc 13.3.0) |
| 結果 |
AC
|
| 実行時間 | 154 ms / 2,000 ms |
| コード長 | 13,519 bytes |
| コンパイル時間 | 1,806 ms |
| コンパイル使用メモリ | 167,444 KB |
| 実行使用メモリ | 30,720 KB |
| 最終ジャッジ日時 | 2024-10-14 01:55:30 |
| 合計ジャッジ時間 | 3,367 ms |
|
ジャッジサーバーID （参考情報） |
judge3 / judge5 |
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| ファイルパターン | 結果 |
|---|---|
| sample | AC * 3 |
| other | AC * 12 |
ソースコード
#include <bits/stdc++.h>
// #include <boost/multiprecision/cpp_int.hpp>
#define int long long
#define inf 1000000007
#define pa pair<int,int>
#define ll long long
#define pal pair<double,double>
#define ppap pair<pa,int>
#define PI 3.14159265358979323846
#define paa pair<int,char>
#define mp make_pair
#define pb push_back
#define EPS (1e-10)
int dx[8]={0,1,0,-1,1,1,-1,-1};
int dy[8]={1,0,-1,0,-1,1,1,-1};
using namespace std;
class pa3{
public:
int x;
int y,z;
pa3(int x=0,int y=0,int z=0):x(x),y(y),z(z) {}
bool operator < (const pa3 &p) const{
if(x!=p.x) return x<p.x;
if(y!=p.y) return y<p.y;
return z<p.z;
//return x != p.x ? x<p.x: y<p.y;
}
bool operator > (const pa3 &p) const{
if(x!=p.x) return x>p.x;
if(y!=p.y) return y>p.y;
return z>p.z;
//return x != p.x ? x<p.x: y<p.y;
}
bool operator == (const pa3 &p) const{
return x==p.x && y==p.y && z==p.z;
}
bool operator != (const pa3 &p) const{
return !( x==p.x && y==p.y && z==p.z);
}
};
class pa4{
public:
int x;
int y,z,w;
pa4(int x=0,int y=0,int z=0,int w=0):x(x),y(y),z(z),w(w) {}
bool operator < (const pa4 &p) const{
if(x!=p.x) return x<p.x;
if(y!=p.y) return y<p.y;
if(z!=p.z)return z<p.z;
return w<p.w;
//return x != p.x ? x<p.x: y<p.y;
}
bool operator > (const pa4 &p) const{
if(x!=p.x) return x>p.x;
if(y!=p.y) return y>p.y;
if(z!=p.z)return z>p.z;
return w>p.w;
//return x != p.x ? x<p.x: y<p.y;
}
bool operator == (const pa4 &p) const{
return x==p.x && y==p.y && z==p.z &&w==p.w;
}
};
class pa2{
public:
int x,y;
pa2(int x=0,int y=0):x(x),y(y) {}
pa2 operator + (pa2 p) {return pa2(x+p.x,y+p.y);}
pa2 operator - (pa2 p) {return pa2(x-p.x,y-p.y);}
bool operator < (const pa2 &p) const{
return y != p.y ? y<p.y: x<p.x;
}
bool operator > (const pa2 &p) const{
return x != p.x ? x<p.x: y<p.y;
}
bool operator == (const pa2 &p) const{
return abs(x-p.x)==0 && abs(y-p.y)==0;
}
bool operator != (const pa2 &p) const{
return !(abs(x-p.x)==0 && abs(y-p.y)==0);
}
};
/*
class Point{
public:
double x,y;
Point(double x=0,double y=0):x(x),y(y) {}
Point operator + (Point p) {return Point(x+p.x,y+p.y);}
Point operator - (Point p) {return Point(x-p.x,y-p.y);}
Point operator * (double a) {return Point(x*a,y*a);}
Point operator / (double a) {return Point(x/a,y/a);}
double absv() {return sqrt(norm());}
double norm() {return x*x+y*y;}
bool operator < (const Point &p) const{
return x != p.x ? x<p.x: y<p.y;
}
bool operator == (const Point &p) const{
return fabs(x-p.x)<EPS && fabs(y-p.y)<EPS;
}
};
typedef Point Vector;
#define pl pair<int,pas>
struct Segment{
Point p1,p2;
};
double dot(Vector a,Vector b){
return a.x*b.x+a.y*b.y;
}
double cross(Vector a,Vector b){
return a.x*b.y-a.y*b.x;
}
bool parareru(Point a,Point b,Point c,Point d){
// if(abs(cross(a-b,d-c))<EPS)cout<<"dd "<<cross(a-b,d-c)<<endl;
return abs(cross(a-b,d-c))<EPS;
}
double distance_ls_p(Point a, Point b, Point c) {
if ( dot(b-a, c-a) < EPS ) return (c-a).absv();
if ( dot(a-b, c-b) < EPS ) return (c-b).absv();
return abs(cross(b-a, c-a)) / (b-a).absv();
}
bool is_intersected_ls(Segment a,Segment b) {
if(a.p1==b.p1||a.p2==b.p1||a.p1==b.p2||a.p2==b.p2) return false;
if(parareru((a.p2),(a.p1),(a.p1),(b.p2))&¶reru((a.p2),(a.p1),(a.p1),(b.p1))){
// cout<<"sss"<<endl;
if(dot(a.p1-b.p1,a.p1-b.p2)<EPS) return true;
if(dot(a.p2-b.p1,a.p2-b.p2)<EPS) return true;
if(dot(a.p1-b.p1,a.p2-b.p1)<EPS) return true;
if(dot(a.p1-b.p2,a.p2-b.p2)<EPS) return true;
return false;
}
else return ( cross(a.p2-a.p1, b.p1-a.p1) * cross(a.p2-a.p1, b.p2-a.p1) < EPS ) && ( cross(b.p2-b.p1, a.p1-b.p1) * cross(b.p2-b.p1, a.p2-b.p1) < EPS );
}
double segment_dis(Segment a,Segment b){
if(is_intersected_ls(a,b))return 0;
double r=distance_ls_p(a.p1, a.p2, b.p1);
r=min(r,distance_ls_p(a.p1, a.p2, b.p2));
r=min(r,distance_ls_p(b.p1, b.p2, a.p2));
r=min(r,distance_ls_p(b.p1, b.p2, a.p1));
return r;
}
Point intersection_ls(Segment a, Segment b) {
Point ba = b.p2-b.p1;
double d1 = abs(cross(ba, a.p1-b.p1));
double d2 = abs(cross(ba, a.p2-b.p1));
double t = d1 / (d1 + d2);
return a.p1 + (a.p2-a.p1) * t;
}
*/
string itos( int i ) {
ostringstream s ;
s << i ;
return s.str() ;
}
int gcd(int v,int b){
if(v>b) return gcd(b,v);
if(v==b) return b;
if(b%v==0) return v;
return gcd(v,b%v);
}
double distans(double x1,double y1,double x2,double y2){
double rr=(x1-x2)*(x1-x2)+(y1-y2)*(y1-y2);
return sqrt(rr);
}
int mod;
int extgcd(int a, int b, int &x, int &y) {
if (b == 0) {
x = 1;
y = 0;
return a;
}
int d = extgcd(b, a%b, y, x);
y -= a/b * x;
return d;
}
pa operator+(const pa & l,const pa & r) {
return {l.first+r.first,l.second+r.second};
}
int pr[1000010];
int inv[1000010];
int beki(int wa,int rr,int warukazu){
if(rr==0) return 1%warukazu;
if(rr==1) return wa%warukazu;
wa%=warukazu;
if(rr%2==1) return ((ll)beki(wa,rr-1,warukazu)*(ll)wa)%warukazu;
ll zx=beki(wa,rr/2,warukazu);
return (zx*zx)%warukazu;
}
double bekid(double w,int r){
if(r==0) return 1.0;
if(r==1) return w;
if(r%2) return bekid(w,r-1)*w;
double f=bekid(w,r/2);
return f*f;
}
int comb(int nn,int rr){
int r=pr[nn]*inv[rr];
r%=mod;
r*=inv[nn-rr];
r%=mod;
return r;
}
void gya(int ert){
pr[0]=1;
for(int i=1;i<ert;i++){
pr[i]=(pr[i-1]*i)%mod;
}
for(int i=0;i<ert;i++) inv[i]=beki(pr[i],mod-2,mod);
}
// cin.tie(0);
// ios::sync_with_stdio(false);
//priority_queue<pa3,vector<pa3>,greater<pa3>> pq;
//sort(ve.begin(),ve.end(),greater<int>());
//----------------kokomade tenpure------------
struct segsum{
// 1
// 2 3
// 4 5 6 7
private:
public:
// (1<<15)=32768
// 1<<16 = 65536
// 1<<17 = 131072
// 1<<18 = 262144
int cor=(1<<18);
vector<int> vec;
vector<int> lazy;
void shoki1(){
vec.resize(2*cor+3, 0);
}
void shoki2(){
for(int i=cor-1;i>0;i--) vec[i]=vec[2*i]+vec[2*i+1];
}
void clear(){
for(int i=0;i<(int)vec.size();i++)vec[i]=0;
}
void updadd(int x,int w){
//x 項目に w加算
x+=cor;
vec[x]+=w;
while(1){
x/=2;
if(x==0) break;
vec[x]=vec[2*x]+vec[2*x+1];
}
}
void updchan(int x,int w){
//x項目をwに変更
x+=cor;
vec[x]=w;
while(1){
x/=2;
if(x==0) break;
vec[x]=vec[2*x]+vec[2*x+1];
}
}
// [a,b)
// k-th node
// k no kukanha [l,r)
int sum(int a,int b,int k=1,int l=0,int r=-10){
if(r<0)r=cor;
// cout<<a<<" "<<b<<" "<<k<<" "<<l<<" "<<r<<endl;
if(a<=l && r<=b){
return vec[k];
}
if(r<=a || b<=l){
return 0;
}
int v1=sum(a,b,k*2,l,(l+r)/2),v2=sum(a,b,k*2+1,(l+r)/2,r);
return v1+v2;
}
};
segsum SE;
vector<int> G[200020];
int ans=0;
void dfs(int r){
ans+=SE.sum(0,r);
// cout<<r<<endl;
SE.updchan(r,1);
for(auto v:G[r])dfs(v);
SE.updchan(r,0);
}
signed main(){
cin.tie(0);
ios::sync_with_stdio(false);
int n;
cin>>n;
for(int i=1;i<n;i++){
int y;
cin>>y;
G[y].pb(i);
}
SE.shoki1();
SE.shoki2();
dfs(0);
cout<<ans<<endl;
return 0;
}