Submission #917129

#	Time	Username	Problem	Language	Result	Execution time	Memory
917129		Whisper	Biochips (IZhO12_biochips)	C++17	100 / 100	353 ms	409152 KiB

biochips

#include <bits/stdc++.h>

using namespace std;
using ll = long long;
using ld = long double;
using T = tuple<ll, ll, ll>;

//#define int long long
#define Base 41
#define sz(a) (int)a.size()
#define FOR(i, a, b) for ( int i = a ; i <= b ; i++ )
#define FORD(i, a, b) for (int i = b; i >= a; i --)
#define REP(i, n) for (int i = 0; i < n; ++i)
#define REPD(i, n) for (int i = n - 1; i >= 0; --i)
#define all(x) x.begin() , x.end()
#define pii pair<int , int>
#define fi first
#define se second
#define Lg(x) 31 - __builtin_clz(x)

#define MASK(i) (1LL << (i))
#define BIT(x, i) (((x) >> (i)) & 1)

constexpr ll LINF = (1ll << 60);
constexpr int INF = (1ll << 30);
constexpr int MAX = 2e5 + 5;
constexpr int Mod = 1e9 + 7;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

void setupIO(){
    #define name "Whisper"
    //Phu Trong from Nguyen Tat Thanh High School for gifted student
    srand(time(NULL));
    cin.tie(nullptr)->sync_with_stdio(false); cout.tie(nullptr);
    //freopen(name".inp", "r", stdin);
    //freopen(name".out", "w", stdout);
    cout << fixed << setprecision(10);
}

template <class X, class Y>
    bool minimize(X &x, const Y &y){
        X eps = 1e-9;
        if (x > y + eps) {x = y; return 1;}
        return 0;
    }

template <class X, class Y>
    bool maximize(X &x, const Y &y){
        X eps = 1e-9;
        if (x + eps < y) {x = y; return 1;}
        return 0;
    }

int N, M;
vector<int> adj[MAX];
int c[MAX];
int tin[MAX], tout[MAX];
int tour[MAX], cnt = 0;

void euler_tour(int u, int p = -1){
    tin[u] = ++cnt;
    tour[cnt] = u;
    for (auto&v : adj[u]) if(v ^ p){
        euler_tour(v, u);
    }
    tout[u] = cnt;
}

int dp[MAX][501];
void Whisper(){
    cin >> N >> M;
    for (int i = 1; i <= N; ++i){
        int p; cin >> p >> c[i];
        adj[p].push_back(i);
        adj[i].push_back(p);
    }
    euler_tour(0);
    memset(dp, -0x3f, sizeof dp);
    dp[cnt + 1][0] = 0;
    for (int i = cnt; i >= 1; --i){
        int u = tour[i];
        for (int v = 0; v <= M; ++v){
            maximize(dp[i][v], dp[i + 1][v]);
            if (v > 0)
                maximize(dp[i][v], dp[tout[u] + 1][v - 1] + c[u]);
        }
    }
    cout << dp[1][M];
}


signed main(){
    setupIO();
    int Test = 1;
//    cin >> Test;
    for ( int i = 1 ; i <= Test ; i++ ){
        Whisper();
        if (i < Test) cout << '\n';
    }
}

• Subtask 1: 100 / 100