Submission #641666

#	Time	Username	Problem	Language	Result	Execution time	Memory
641666		piOOE	Toy Train (IOI17_train)	C++17	5 / 100	2084 ms	1860 KiB

train

#include <bits/stdc++.h>
#include "train.h"

using namespace std;
using ll = long long;

std::vector<int> who_wins(std::vector<int> a, std::vector<int> r, std::vector<int> A, std::vector<int> B) {
    int n = a.size(), m = A.size();
    vector<vector<int>> g(n);
    for (int i = 0; i < m; ++i) {
        g[A[i]].push_back(B[i]);
    }
    vector<int> ans(n);
    for (int root = 0; root < n; ++root) {
        vector<bool> dp(n), used(n);
        vector<int> stk, last = {-1};
        vector<int> in_stk(n, -1);
        auto dfs = [&](auto self, int v) -> void {
            used[v] = true;
            in_stk[v] = stk.size();
            stk.push_back(v);
            if (r[v]) {
                last.push_back(last.size() - 1);
            } else {
                last.push_back(last.back());
            }
            for (int to: g[v]) {
                if (in_stk[to] != -1) {
                    if (a[v] ^ (last.back() < in_stk[to])) {
                        dp[v] = true;
                    }
                } else {
                    if (!used[to]) {
                        self(self, to);
                    }
                    if (a[v] ^ a[to] ^ dp[to]) {
                        dp[v] = true;
                    }
                }
            }
            stk.pop_back();
            last.pop_back();
            in_stk[v] = -1;
        };
        dfs(dfs, root);
        ans[root] = dp[root] ^ a[root] ^ 1;
    }
    return ans;
}

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