Submission #834632

#	Time	Username	Problem	Language	Result	Execution time	Memory
834632		Essa2006	Magic Tree (CEOI19_magictree)	C++17	100 / 100	124 ms	38944 KiB

magictree

#include<bits/stdc++.h>
using namespace std;
#define int long long
#define endl '\n'
#define FF first
#define SS second
#define all(a) a.begin(), a.end()
#define mod (ll)(1000000007)
int n, m, k;
vector<int>P, Order;
vector<array<int, 2>>Q;
vector<vector<int>>A;
vector<map<int, int>>dp;

void pre(){
    P.clear(), Order.clear(), Q.clear(), A.clear(), dp.clear();
    P.resize(n+1), Q.resize(n+1), A.resize(n+1), dp.resize(n+1);
}

void dfs(int u){
    for(int i=0;i<A[u].size();i++){
        int v=A[u][i];
        if(v!=P[u])
            dfs(v);
    }
    Order.push_back(u);
}
signed main(){
    ios_base::sync_with_stdio(0);cin.tie(0);
    cin>>n>>m>>k;
    pre();
    for(int i=2;i<=n;i++){
        cin>>P[i];
        int u=i, v=P[i];
        A[u].push_back(v);
        A[v].push_back(u);
    }
    for(int j=0;j<m;j++){
        int v, d, c;
        cin>>v>>d>>c;
        Q[v]={d, c};
    }
    dfs(1);
    for(int kk=0;kk<n;kk++){
        int u=Order[kk], mx=0;
        for(auto v:A[u]){
            if(v==P[u])
                continue;
            if(dp[v].size()>dp[mx].size())
                mx=v;
        }
        if(mx)
            swap(dp[u], dp[mx]);
        for(auto v:A[u]){
            if(v==P[u] || v==mx)
                continue;
            for(auto it:dp[v]){
                int d=it.FF, benf=it.SS;
                dp[u][d]+=benf;
            }
        }
        int d=Q[u][0], benf=Q[u][1];
        if(d){
            dp[u][d]+=benf;
            auto it=dp[u].upper_bound(d);
            int mx_x=0, pre=0;
            for(;it!=dp[u].end();it++){
                pre+=it->SS;
                if(benf<pre)
                    break;
                mx_x=it->FF;
            }
            while(true){
                it=dp[u].upper_bound(d);
                if(it==dp[u].end())
                    break;
                if(it->FF>mx_x){
                    it->SS=pre-benf;
                    break;
                }
                dp[u].erase(it);
            }
        }
    }
    int ans=0;
    for(auto it:dp[1]){
        ans+=it.SS;
    }
    cout<<ans;
}

Compilation message (stderr)

magictree.cpp: In function 'void dfs(long long int)':
magictree.cpp:21:18: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   21 |     for(int i=0;i<A[u].size();i++){
      |                 ~^~~~~~~~~~~~

• Subtask 1: 6 / 6
• Subtask 2: 3 / 3
• Subtask 3: 11 / 11
• Subtask 4: 12 / 12
• Subtask 5: 16 / 16
• Subtask 6: 13 / 13
• Subtask 7: 22 / 22
• Subtask 8: 17 / 17