Submission #338418

#	Time	Username	Problem	Language	Result	Execution time	Memory
338418		talant117408	Biochips (IZhO12_biochips)	C++17	0 / 100	4 ms	5100 KiB

biochips

/*
    Code written by Talant I.D.
*/
#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>
#include <ext/rope>
//#include <ext/pb_ds/assoc_container.hpp>
 
//using namespace __gnu_pbds;
using namespace __gnu_cxx;
using namespace std;
 
//typedef tree <int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> indexed_set;
typedef long long ll;
typedef pair <int, int> pii;
typedef pair <ll, ll> pll;
  
#define precision(n) fixed << setprecision(n)
#define pb push_back
#define ub upper_bound
#define lb lower_bound
#define mp make_pair
#define eps (double)1e-9
#define PI 2*acos(0.0)
#define endl "\n"
#define sz(v) int((v).size())
#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(),v.rend()
#define do_not_disturb ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define OK cout << "OK" << endl;
  
inline bool isvowel(char ch){
    ch = tolower(ch);
    return (ch == 'a' || ch == 'e' || ch == 'i' || ch == 'o' || ch == 'u');
}
  
inline bool isprime(int n){
    if(n < 2 || (n%2 == 0 && n != 2)) return false;
    for(int i = 3; i*i <= n; i++)
        if(n%i == 0) return false;
    return true;
}
 
class Union{
    private:
        vector <int> saizu, link;
    public:
        Union(int n){
            saizu.assign(n, 1); link.resize(n); 
            iota(all(link), 0);
        }
        int find(int n){
            if(link[n] == n) return n;
            return link[n] = find(link[n]);
        }
        int same(int a, int b){
            return find(a) == find(b);
        }
        void unite(int a, int b){
            if(same(a, b)) return;
             
            a = find(a); b = find(b);
            if(saizu[a] < saizu[b]) swap(a, b);
             
            saizu[a] += saizu[b];
            link[b] = a;
        }
        int getsize(int a){
            return saizu[find(a)];
        }
};
 
const int mod = 1e9+7;
 
ll mode(ll a){
    a %= mod;
    if(a < 0) a += mod;
    return a;
}
 
ll subt(ll a, ll b){
    return mode(mode(a)-mode(b));
}
 
ll add(ll a, ll b){
    return mode(mode(a)+mode(b));
}
 
ll mult(ll a, ll b){
    return mode(mode(a)*mode(b));
}
 
ll binpow(ll a, ll b){
    ll res = 1;
    while(b){
        if(b&1) res = mult(res, a);
        a = mult(a, a);
        b >>= 1;
    }
    return res;
}

const int N = 2e5+7;
vector <vector <ll>> graph(N);
ll tin[N], tout[N], timer, up[N][20];

void dfs(int v, int p){
    up[v][0] = p;
    tin[v] = ++timer;
    for(ll i = 1; i < 20; i++){
        up[v][i] = up[up[v][i-1]][i-1];
    }
    for(auto to : graph[v]){
        if(to != p){
            dfs(to, v);
        }
    }
    tout[v] = ++timer;
}

bool upper(int a, int b){
    return tin[a] <= tin[b] && tout[a] >= tout[b];
}

int lca(int a, int b){
    if(upper(a, b)) return a;
    if(upper(b, a)) return b;
    for(ll i = 19; i >= 0; i--){
        if(!upper(up[a][i], b)) a = up[a][i];
    }
    return up[a][0];
}

int main(){
    do_not_disturb
    
    ll n, m;
    cin >> n >> m;
    vector <ll> par(n+1), memory(n+1);
    ll root = 1;
    for(int i = 1; i <= n; i++){
        cin >> par[i] >> memory[i];
        if(par[i]){
            graph[par[i]].pb(i);
        }
        else{
            root = i;
        }
    }
    
    dfs(root, root);
    
    if(n < 21 && m < 21){
        ll ans = 0;
        for(int mask = 0; mask < (1<<n); mask++){
            if(__builtin_popcount(mask) != m) continue;
            vector <ll> vec;
            ll flag = 0, res = 0;
            for(ll i = 1; i <= n; i++){
                if(mask&(1<<(i-1))){
                    vec.pb(i);
                    res += memory[i];
                }
            }
            for(ll i = 0; i < m; i++){
                for(ll j = i+1; j < m; j++){
                    if(upper(vec[i], vec[j]) || upper(vec[j], vec[i])) flag++;
                }
            }
            if(!flag) ans = max(ans, res);
        }
        cout << ans;
    }
    
    return 0;
}

• Subtask 1: 0 / 100