結果
問題 | No.778 クリスマスツリー |
ユーザー |
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提出日時 | 2020-05-24 02:27:47 |
言語 | C++14 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 101 ms / 2,000 ms |
コード長 | 2,268 bytes |
コンパイル時間 | 1,644 ms |
コンパイル使用メモリ | 170,036 KB |
実行使用メモリ | 25,048 KB |
最終ジャッジ日時 | 2024-10-09 16:26:00 |
合計ジャッジ時間 | 4,078 ms |
ジャッジサーバーID (参考情報) |
judge3 / judge4 |
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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>using namespace std;// #define int long long#define rep(i, n) for (long long i = (long long)(0); i < (long long)(n); ++i)#define reps(i, n) for (long long i = (long long)(1); i <= (long long)(n); ++i)#define rrep(i, n) for (long long i = ((long long)(n)-1); i >= 0; i--)#define rreps(i, n) for (long long i = ((long long)(n)); i > 0; i--)#define irep(i, m, n) for (long long i = (long long)(m); i < (long long)(n); ++i)#define ireps(i, m, n) for (long long i = (long long)(m); i <= (long long)(n); ++i)#define SORT(v, n) sort(v, v + n);#define REVERSE(v, n) reverse(v, v+n);#define vsort(v) sort(v.begin(), v.end());#define all(v) v.begin(), v.end()#define mp(n, m) make_pair(n, m);#define cout(d) cout<<d<<endl;#define coutd(d) cout<<std::setprecision(10)<<d<<endl;#define cinline(n) getline(cin,n);#define replace_all(s, b, a) replace(s.begin(),s.end(), b, a);#define PI (acos(-1))#define FILL(v, n, x) fill(v, v + n, x);#define sz(x) long long(x.size())using ll = long long;using vi = vector<int>;using vvi = vector<vi>;using vll = vector<ll>;using vvll = vector<vll>;using pii = pair<int, int>;using pll = pair<ll, ll>;using vs = vector<string>;using vpll = vector<pair<ll, ll>>;using vtp = vector<tuple<ll,ll,ll>>;using vb = vector<bool>;template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }const ll INF = 1e9;const ll MOD = 1e9+7;const ll LINF = 1e18;template<typename T>struct BIT {int n;vector<T> d;BIT(int n=0):n(n),d(n+1) {}void add(int i, T x=1) {for (; i <= n; i += i&-i) {d[i] += x;}}T sum(int i) {T x = 0;for (; i; i -= i&-i) {x += d[i];}return x;}T sum(int l, int r) {return sum(r) - sum(l-1);}};BIT<ll> bit(200100);vll G[200100];ll ans=0;void dfs(ll v){ans+=bit.sum(v);bit.add(v+1);for(auto nv: G[v]) dfs(nv);bit.add(v+1,-1);}signed main(){cin.tie( 0 ); ios::sync_with_stdio( false );ll n; cin>>n;irep(i,1,n){ll a; cin>>a;G[a].push_back(i); // aは頂点iの親なので、a=>iに辺が張られる}dfs(0);cout<<ans<<endl;}