Submission #68946

#	Time	Username	Problem	Language	Result	Execution time	Memory
68946		aquablitz11	Toy Train (IOI17_train)	C++14	0 / 100	2084 ms	112096 KiB

train

#include <bits/stdc++.h>
#include "train.h"
using namespace std;
 
using pii = pair<int, int>;
 
const int N = 5e3+10;
int n, m;
vector<int> G[N], R[N];
vector<int> A, C;
bool can[N][N];
int cnt[N][N], need[N];

void dfs(int u, int p)
{
    if (C[u] && p < n) return void(dfs(u, n));
    if (p < 0) return;
    if (can[u][p]) return;
    can[u][p] = true;
    for (auto v : G[u]) dfs(v, p-1);
}

vector<int> who_wins(vector<int> AA, vector<int> CC, vector<int> U, vector<int> V)
{
    swap(AA, A), swap(CC, C);
    // input
    n = A.size();
    m = U.size();
    for (int i = 0; i < m; ++i) {
        G[U[i]].push_back(V[i]);
        R[V[i]].push_back(U[i]);
    }
    // find reachable states
    for (int i = 0; i < n; ++i) {
        need[i] = A[i] ? (int)G[i].size() : 1;
        dfs(i, n);
    }

    // winning position
    vector<int> ans(n, 1);
    queue<pii> Q;
    for (int i = 0; i < n; ++i)
        if (can[i][0]) Q.emplace(i, 0);

    while (!Q.empty()) {
        int u = Q.front().first, p = Q.front().second;
        Q.pop();
        if (p == n) ans[u] = 0;
        int pl = 1, pr = n;
        if (!C[u]) pl = pr = p+1;
        for (auto v : R[u]) {
            for (int np = pl; np <= pr && np <= n; ++np) {
                ++cnt[v][np];
                if (can[v][n] && cnt[v][np] == need[v]) {
                    can[v][np] = false;
                    Q.emplace(v, np);
                }
            }
        }
    }
 
    return ans;
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 10
• Subtask 3: 0 / 11
• Subtask 4: 0 / 11
• Subtask 5: 0 / 12
• Subtask 6: 0 / 51