Submission #1013349

#	Time	Username	Problem	Language	Result	Execution time	Memory
1013349		Luvidi	Dreaming (IOI13_dreaming)	C++17	18 / 100	32 ms	16168 KiB

dreaming

#include "dreaming.h"
#include <bits/stdc++.h>
using namespace std;

#define pb push_back
#define pii pair<int,int>

const int maxn=1e5;
vector<pii> adj[maxn];
int d[maxn][2],d2[maxn],d3[maxn];
bool vis[maxn];

void dfs(int v,int p){
    vis[v]=1;
    vector<int> z;
    for(auto [i,x]:adj[v])if(i!=p){
        dfs(i,v);
        z.pb(d[i][0]+x);
    }
    sort(z.rbegin(),z.rend());
    for(int i=0;i<z.size()&&i<2;i++)d[v][i]=z[i];
}

void dfs2(int v,int p,int r){
    d3[r]=min(d3[r],max(d[v][0],d2[v]));
    for(auto [i,x]:adj[v])if(i!=p){
        if(d[v][0]==d[i][0]+x){
            d2[i]=x+max(d[v][1],d2[v]); 
        }else{
            d2[i]=x+max(d[v][0],d2[v]); 
        }
        dfs2(i,v,r);   
    }
}


int travelTime(int n, int m, int l, int a[], int b[], int t[]) {
    for(int i=0;i<m;i++){
        adj[a[i]].pb({b[i],t[i]});
        adj[b[i]].pb({a[i],t[i]});
    }
    vector<int> v;
    for(int i=0;i<n;i++){
        if(!vis[i]){
            dfs(i,-1);
            d3[i]=1e9;
            dfs2(i,-1,i);
            v.pb(d3[i]);
        }
    }
    sort(v.rbegin(),v.rend());
    if(v.size()==1){
        return v[0];
    }else if(v.size()==2){
        return v[0]+v[1]+l;
    }else{
        return max(v[0],v[2]+l)+v[1]+l;
    }   
}

Compilation message (stderr)

dreaming.cpp: In function 'void dfs(int, int)':
dreaming.cpp:21:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   21 |     for(int i=0;i<z.size()&&i<2;i++)d[v][i]=z[i];
      |                 ~^~~~~~~~~

• Subtask 1: 0 / 14
• Subtask 2: 0 / 10
• Subtask 3: 0 / 23
• Subtask 4: 18 / 18
• Subtask 5: 0 / 12
• Subtask 6: 0 / 23