Submission #1103868

# Submission time Handle Problem Language Result Execution time Memory
1103868 2024-10-22T05:02:12 Z dubabuba Dreaming (IOI13_dreaming) C++14
0 / 100
26 ms 12624 KB
#include "dreaming.h"
#include <bits/stdc++.h>

using namespace std;

#define ff first
#define ss second
#define MP make_pair

typedef pair<int, int> pii;

const int inf = 1e9 + 10;
const int mxn = 1e5 + 10;
vector<pii> adj[mxn];
int m1[mxn], m2[mxn];

void update(int &M1, int &M2, int sus) {
    if(sus > M1) {
        M2 = M1;
        M1 = sus;
    }
    else if(sus > M2) {
        M2 = sus;
    }
}

void maxer(int &MAX, int CMP) { if(MAX < CMP) MAX = CMP; }

int max_dfs(int u, int par = -1) {
    if(adj[u].size() == 1)
        m1[u] = 0;
    for(pii e : adj[u]) {
        int v = e.ff;
        int c = e.ss;
        if(v == par) continue;
        if(m1[v] > -1) continue;

        int t = max_dfs(v, u) + c;
        update(m1[u], m2[u], t);
    }

    // cout << u << ": " << m1[u] << ' ' << m2[u] << endl;
    return m1[u];
}

int fix_dfs(int u, int prv = -1) {
    int opt = -1;
    int sus = m1[u];
    int len = -1;

    for(pii e : adj[u]) {
        int v = e.ff;
        int c = e.ss;
        if(v == prv) continue;
        if(m1[v] + c < m1[u]) continue;
        
        int NEW = max(m1[v], m2[u] + c);
        if(NEW < sus) {
            sus = NEW;
            opt = v;
            len = c;
        }
    }

    if(opt == -1) return u;
    update(m1[opt], m2[opt], sus);
    return fix_dfs(opt, u);
}

int travelTime(int N, int M, int L, int A[], int B[], int T[]) {
    for(int i = 0; i < M; i++) {
        int u = A[i];
        int v = B[i];
        int c = T[i];
        // cout << u << ' ' << v << ": " << c << endl;
        adj[u].push_back(MP(v, c));
        adj[v].push_back(MP(u, c));
    }

    for(int i = 0; i < N; i++) {
        m1[i] = m2[i] = -1;
    }

    vector<int> upt;
    for(int i = 0; i < N; i++) {
        if(m1[i] > -1) continue;
        // cout << "root = " << i << endl;
        max_dfs(i);
        // cout << "------\n";
        upt.push_back(i);
    }

    int ans = 0;
    vector<int> roots;
    for(int x : upt) {
        int y = fix_dfs(x);
        roots.push_back(y);
        // cout << x << ": " << y << endl;
        maxer(ans, m1[y] + m2[y]);
    }

    if(roots.size() == 1)
        return ans;

    pii M1 = MP(-inf, -1);
    pii M2 = MP(-inf, -1);
    pii M3 = MP(-inf, -1);

    for(int u : roots) {
        pii cur = MP(m1[u], u);
        if(cur > M1) {
            M3 = M2;
            M2 = M1;
            M1 = cur;
        }
        else if(cur > M2) {
            M3 = M2;
            M2 = cur;
        }
        else if(cur > M3) {
            M3 = cur;
        }
    }

    maxer(ans, M1.ff + M2.ff + L);
    maxer(ans, M2.ff + M3.ff + 2 * L);
    return ans;
}

Compilation message

dreaming.cpp: In function 'int fix_dfs(int, int)':
dreaming.cpp:49:9: warning: variable 'len' set but not used [-Wunused-but-set-variable]
   49 |     int len = -1;
      |         ^~~
# Verdict Execution time Memory Grader output
1 Incorrect 26 ms 12624 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 4432 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 26 ms 12624 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 12 ms 7688 KB Output is correct
2 Correct 12 ms 7632 KB Output is correct
3 Correct 13 ms 7664 KB Output is correct
4 Correct 13 ms 7636 KB Output is correct
5 Correct 14 ms 7632 KB Output is correct
6 Correct 15 ms 8144 KB Output is correct
7 Correct 15 ms 7760 KB Output is correct
8 Correct 14 ms 7636 KB Output is correct
9 Correct 21 ms 7604 KB Output is correct
10 Correct 14 ms 7756 KB Output is correct
11 Correct 2 ms 4432 KB Output is correct
12 Correct 3 ms 5692 KB Output is correct
13 Correct 4 ms 5576 KB Output is correct
14 Correct 5 ms 5716 KB Output is correct
15 Correct 4 ms 5680 KB Output is correct
16 Correct 4 ms 5576 KB Output is correct
17 Correct 4 ms 5576 KB Output is correct
18 Correct 5 ms 5576 KB Output is correct
19 Correct 4 ms 5576 KB Output is correct
20 Correct 2 ms 4432 KB Output is correct
21 Incorrect 1 ms 4600 KB Output isn't correct
22 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 4432 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 26 ms 12624 KB Output isn't correct
2 Halted 0 ms 0 KB -