oj.uz

답안 #510151

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
510151 2022-01-14T18:12:46 Z Yazan_Alattar Islands (IOI08_islands) C++14
0 / 100
 2000 ms 131072 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)
{
    assert(timer < 1e5);
    ++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;
assert(timer < 1e5);
    ++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)
{
    assert(timer < 1e5);
    ++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)
{
    assert(timer < 1e5);
    ++timer;
    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;
        }
        timer = 0; /////================
        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);
        timer = 0; /////================
        pair <ll,ll> nodea = calc(edge.F);
        timer = 0; /////================
        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();
    }
    cout << ans << endl;
    return 0;
}

Subtask #1
0 / 33.0

# 결과 실행 시간 메모리 Grader output
1 Execution timed out 2078 ms 23756 KB Time limit exceeded
2 Runtime error 29 ms 48204 KB Execution killed with signal 6
3 Incorrect 11 ms 23884 KB Output isn't correct
4 Execution timed out 2075 ms 23756 KB Time limit exceeded
5 Runtime error 39 ms 63940 KB Execution killed with signal 6
6 Execution timed out 2069 ms 23756 KB Time limit exceeded
7 Execution timed out 2067 ms 23756 KB Time limit exceeded
8 Execution timed out 2065 ms 23724 KB Time limit exceeded
9 Execution timed out 2083 ms 23756 KB Time limit exceeded
10 Execution timed out 2086 ms 23832 KB Time limit exceeded
11 Execution timed out 2084 ms 23804 KB Time limit exceeded

Subtask #2
0 / 3.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 13 ms 23948 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
0 / 4.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 41 ms 60292 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -

Subtask #4
0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 39 ms 54404 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -

Subtask #5
0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 67 ms 63700 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -

Subtask #6
0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 103 ms 83048 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -

Subtask #7
0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 172 ms 110324 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -

Subtask #8
0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 339 ms 131072 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -

Subtask #9
0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 357 ms 131072 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -