oj.uz

답안 #510156

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
510156 2022-01-14T18:16:19 Z Yazan_Alattar Islands (IOI08_islands) C++14
0 / 100
 2000 ms 131076 KB 
#include <iostream>
#include <fstream>
#include <vector>
#include <cstring>
#include <algorithm>
#include <set>
#include <map>
#include <queue>
#include <list>
#include <utility>
#include <cmath>
#include <numeric>
#include <assert.h>
using namespace std;
typedef long long ll;
#define F first
#define S second
#define pb push_back
#define endl "\n"
#define all(x) x.begin(), x.end()
const int M = 1000007;
const ll inf = 1e18;
const ll mod = 1e9 + 7;
const double pi = acos(-1);
const int dx[] = {1, 0, -1, 0}, dy[] = {0, 1, 0, -1};

vector < pair < ll, pair <int,int> > > edges;
vector < pair <int,ll> > adj[M];
vector <int> nodes;
pair <int,int> edge;
ll n, cost[M], mxchild[M], p[M], ans, edgecost, root, timer;
bool vist[M];

void get(int node)
{
    ++timer;
    nodes.pb(node);
    vist[node] = 1;
    for(auto i : adj[node]){
        edges.pb({i.S, {node, i.F}});
        if(!vist[i.F]) get(i.F);
    }
    return;
}

void dfs(int node, ll cur)
{
//    cout << node << " " << edge.F << " " << edge.S << endl;
    ++timer;
    cost[node] = cur;
    mxchild[node] = cur;
    for(auto i : adj[node]){
        if(i.F == p[node] || ((edge == make_pair(node, i.F) || edge == make_pair(i.F, node)) && edgecost == i.S)) continue;
        p[i.F] = node;
        dfs(i.F, cur + i.S);
        mxchild[node] = max(mxchild[node], mxchild[i.F]);
    }
    return;
}

pair <int,int> calc(int node)
{
    ++timer;
    pair <ll,ll> ret;
    int cur = node;
    while(p[cur] != root) cur = p[cur];
    ret.F = cost[node] - cost[cur];
    ret.S = mxchild[node];
    return ret;
}

ll best(int node)
{
    ll ret = 0;
    for(auto i : adj[node]){
        if(i.F == p[node]) continue;
        if(i.F == edge.F || i.F == edge.S) return -1;
        ll x = best(i.F);
        if(x == -1 && node != 1) return -1;
        else ret = max(ret, best(i.F));
    }
    return ret;
}

int main()
{
    ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    cin >> n;
    for(int i = 1; i <= n; ++i){
        ll x, y;
        cin >> x >> y;
//        x = (i % n) + 1;
//        y = i;
        adj[x].pb({i, y});
        adj[i].pb({x, y});
    }
    for(int j = 1; j <= n; ++j){
        if(vist[j]) continue;
        timer = 0;
        get(j);
        sort(all(edges), greater < pair < ll, pair <int,int> > > ());
        edge = {edges.back().S.F, edges.back().S.S};
        edgecost = edges.back().F;
        root = 0;
        for(auto i : nodes) if(i != edge.F && i != edge.S) {root = i; break;}
        if(root == 0){
//            for(auto i : edges) cout << i.S.F << " " << i.S.S << " " << i.F << endl;
            ans += edges[0].F;
            continue;
        }
        dfs(root, 0);
        ll mx1 = 0, mx2 = 0, mx = 0;
        for(auto i : nodes){
            if(cost[i] > mx1) mx2 = mx1, mx1 = cost[i];
            else if(cost[i] > mx2) mx2 = cost[i];
        }
        mx = mx1 + mx2;
        mx1 = best(root);
        pair <ll,ll> nodea = calc(edge.F);
        pair <ll,ll> nodeb = calc(edge.S);
        mx = max(mx, nodea.F + nodeb.S + edges.back().F);
        mx = max(mx, nodea.F + nodeb.F + edges.back().F);
        mx = max(mx, nodea.S + nodeb.F + edges.back().F);
        mx = max(mx, nodea.S + nodeb.S + edges.back().F);
        mx = max(mx, mx1 + cost[edge.F] + nodeb.S + edges.back().F);
        mx = max(mx, mx1 + cost[edge.F] + nodeb.F + edges.back().F);
        mx = max(mx, mx1 + nodea.F + cost[edge.S] + edges.back().F);
        mx = max(mx, mx1 + nodea.S + cost[edge.S] + edges.back().F);
        ans += mx;
        edges.clear();
        nodes.clear();
    }
    assert(timer > 1e5);
    cout << ans << endl;
    return 0;
}

Subtask #1
0 / 33.0

# 결과 실행 시간 메모리 Grader output
1 Execution timed out 2083 ms 23756 KB Time limit exceeded
2 Execution timed out 2051 ms 23756 KB Time limit exceeded
3 Runtime error 31 ms 48256 KB Execution killed with signal 6
4 Execution timed out 2078 ms 23756 KB Time limit exceeded
5 Runtime error 69 ms 131076 KB Execution killed with signal 9
6 Execution timed out 2081 ms 23756 KB Time limit exceeded
7 Execution timed out 2075 ms 23756 KB Time limit exceeded
8 Execution timed out 2082 ms 23756 KB Time limit exceeded
9 Execution timed out 2093 ms 23756 KB Time limit exceeded
10 Execution timed out 2085 ms 23756 KB Time limit exceeded
11 Execution timed out 2047 ms 23780 KB Time limit exceeded

Subtask #2
0 / 3.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 30 ms 48408 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -

Subtask #3
0 / 4.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 68 ms 131076 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -

Subtask #4
0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 266 ms 131076 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -

Subtask #5
0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 45 ms 31468 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #6
0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 379 ms 131076 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -

Subtask #7
0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 170 ms 131076 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -

Subtask #8
0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 482 ms 131076 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -

Subtask #9
0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 319 ms 131076 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -