Submission #1212423

#	Time	Username	Problem	Language	Result	Execution time	Memory
1212423		Aviansh	Closing Time (IOI23_closing)	C++20	35 / 100	1042 ms	2162688 KiB

closing

#include "closing.h"

#include <vector>
#include <bits/stdc++.h>

using namespace std;

void dfs(int st, vector<array<int,2>>g[], int p, long long dist[], long long d){
    dist[st]=d;
    for(array<int,2>e:g[st]){
        if(e[0]==p)
            continue;
        dfs(e[0],g,st,dist,d+e[1]);
    }
}
vector<int>xypath;
void dfsxy(int st, vector<array<int,2>>g[], int p, vector<int>&path, int y){
    path.push_back(st);
    if(st==y){
        xypath.clear();
        for(int i : path){
            xypath.push_back(i);
        }
    }
    for(array<int,2>e : g[st]){
        if(e[0]==p)
            continue;
        dfsxy(e[0],g,st,path,y);
    }
    path.pop_back();
}

int max_score(int n, int x, int y, long long k, vector<int> u, vector<int> v, vector<int> w) {
    vector<array<int,2>>g[n];
    int m = u.size();
    for(int i = 0;i<m;i++){
        g[u[i]].push_back({v[i],w[i]});
        g[v[i]].push_back({u[i],w[i]});
    }
    long long distx[n], disty[n];
    dfs(x,g,-1,distx,0);
    dfs(y,g,-1,disty,0);
    long long cost1[n],cost2[n];
    for(int i = 0;i<n;i++){
        cost1[i]=min(distx[i],disty[i]);
        cost2[i]=max(distx[i],disty[i])-cost1[i];
    }
    vector<int>pt;
    dfsxy(x,g,-1,pt,y);
    //case 1:
    int ans1 = 0;
    //only till level 1.
    priority_queue<long long,vector<long long>,greater<long long>>pq;
    for(int i = 0;i<n;i++){
        pq.push(cost1[i]);
    }
    long long curk = 0;
    while(curk<=k&&pq.size()){
        long long a = pq.top();
        pq.pop();
        if(curk+a>k)
            break;
        ans1++;
        curk+=a;
    }
    //case 2:
    bool man[n];
    fill(man,man+n,0);
    for(int i : xypath){
        man[i]=1;
    }
    long long dp[n][n*2+1];
    for(int i = 0;i<n;i++){
        fill(dp[i],dp[i]+n*2+1,2e18);
        dp[i][0]=0;
        if(man[i]){
            dp[i][0]=2e18;
        }
    }
    dp[0][1]=cost1[0];
    dp[0][2]=cost1[0]+cost2[0];
    for(int i = 1;i<n;i++){
        for(int j = 1;j<=2*n;j++){
            if(man[i]){
                //must take atleast one.
                dp[i][j]=dp[i-1][j-1]+cost1[i];
            }
            else{
                dp[i][j]=min({dp[i-1][j],dp[i-1][j-1]+cost1[i]});
            }
            if(j>1){
                dp[i][j]=min(dp[i][j],dp[i-1][j-2]+cost1[i]+cost2[i]);
            }
            dp[i][j]=min((long long)2e18,dp[i][j]);
        }
    }
    int ans2 = 0;
    for(int j = 0;j<=2*n;j++){
        if(dp[n-1][j]<=k){
            ans2=max(ans2,j);
        }
    }
    return max(ans1,ans2);
}

• Subtask 0: 0 / 0
• Subtask 1: 0 / 8
• Subtask 2: 9 / 9
• Subtask 3: 12 / 12
• Subtask 4: 14 / 14
• Subtask 5: 0 / 9
• Subtask 6: 0 / 11
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 17