Submission #1079512

#	Time	Username	Problem	Language	Result	Execution time	Memory
1079512		mindiyak	Dreaming (IOI13_dreaming)	C++14	0 / 100	1056 ms	65536 KiB

dreaming

#include "dreaming.h"
#include <bits/stdc++.h>
#include <string>
#include <iostream>
#include <cmath>
#include <numeric>
#include <iomanip>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<int, int> pi;
typedef pair<int, int> pl;
typedef pair<ld, ld> pd;
typedef vector<int> vi;
typedef vector<bool> vb;
typedef vector<vector<int>> vvi;
typedef vector<ld> vd;
typedef vector<long> vl;
typedef vector<ull> vull;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<vpi> vvpi;
#define FOR(i, a, b) for (int i = a; i < (b); i++)
#define F0R(i, a) for (int i = 0; i < (a); i++)
#define FORd(i, a, b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i, a) for (int i = (a)-1; i >= 0; i--)
#define trav(a, x) for (auto &a : x)
#define uid(a, b) uniform_int_distribution<int>(a, b)(rng)
#define len(x) (int)(x).size()
#define mp make_pair
#define pb push_back
#define F first
#define nl endl
#define S second
#define lb lower_bound
#define ub upper_bound
#define aint(x) x.begin(), x.end()
#define raint(x) x.rbegin(), x.rend()
#define ins insert
const int MOD = 1000000007;

vi visited,visited2;
vvpi paths;
int maxdist = 0;
int node = 0;
set<int> remember;

void dfs(int pos,int prev,int dist,int can,set<int> path){
    if(visited[pos])return;
    visited[pos] = 1;
    if(can)visited2[pos] = 1;
    if(can)path.insert(pos);

    if(dist > maxdist){
        node = pos;
        maxdist = dist;
        if(can)remember = path;
    }

    for(auto edge:paths[pos]){
        if(edge.F == prev)continue;
        dfs(edge.F,pos,dist+edge.S,can,path);
    }
}

void dfs2(int pos,int prev,int dist,int to_go){
    if(remember.count(pos) == 0)return;

    if(maxdist > max(to_go,dist)){
        maxdist = max(to_go,dist);
        node = pos;
    }

    for(auto edge:paths[pos]){
        if(edge.F == prev)continue;
        dfs2(edge.F,pos,dist+edge.S,to_go-edge.S);
    }
}

int travelTime(int n, int m, int L, int A[], int B[], int T[]) {
    if(n==1)return 0;
    paths = vvpi(n);
    visited2 = vi(n,0);
    vi distances(n,0);

    FOR(i,0,m){
        paths[A[i]].pb({B[i],T[i]});
        paths[B[i]].pb({A[i],T[i]});
    }

    for(int i=0;i<n;i++){
        if(visited2[i])continue;

        visited = vi(n,0);
        maxdist = 0;
        node = i;
        set<int> temp;
        dfs(i,-1,0,0,temp);

        cerr << i << " " << node << " " << maxdist << endl;

        visited = vi(n,0);
        int head = node;
        node = i;
        maxdist = 0;
        remember.clear();
        dfs(head,-1,0,1,temp);

        cerr << "found other corner " << " " << node << " " << maxdist << endl;

        head = node;
        dfs2(head,-1,0,maxdist);

        cerr << "mid point " << " " << node << " " << maxdist << endl;

        visited = vi(n,0);
        head = node;
        maxdist = 0;
        dfs(head,-1,0,0,temp);

        cerr << "verifying " << " " << node << " " << maxdist << endl;

        distances[i] = maxdist;

        FOR(i,0,n)cerr << visited[i] << " ";
        cerr << endl << endl;
    }

    sort(distances.rbegin(),distances.rend());

    if(m == n-1)return distances[0];

    return distances[0] + distances[1] + L;
    
}

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