Submission #1025462

#	Time	Username	Problem	Language	Result	Execution time	Memory
1025462		shiomusubi496	Toy Train (IOI17_train)	C++17	100 / 100	1614 ms	2268 KiB

train

#include "train.h"

#include <bits/stdc++.h>

#define rep(i, n) for (int i = 0; i < (int)(n); ++i)
#define rep2(i, a, b) for (int i = (int)(a); i < (int)(b); ++i)
#define rrep(i, n) for (int i = (int)(n) - 1; i >= 0; --i)
#define rrep2(i, a, b) for (int i = (int)(b) - 1; i >= (int)(a); --i)
#define all(v) begin(v), end(v)

using namespace std;

template<class T, class U> bool chmin(T& a, const U& b) { return a > b ? a = b, true : false; }
template<class T, class U> bool chmax(T& a, const U& b) { return a < b ? a = b, true : false; }

using ll = long long;

std::vector<int> who_wins(std::vector<int> a, std::vector<int> r, std::vector<int> u, std::vector<int> v) {
    vector<int> ids(a.size()); iota(all(ids), 0);
    vector<int> ans(a.size());
    while (true) {
        int n = a.size(), m = u.size();
        vector<vector<int>> g(n), rg(n);
        rep (i, m) {
            g[u[i]].push_back(v[i]);
            rg[v[i]].push_back(u[i]);
        }
        auto calc = [&](vector<int> r, bool f) -> vector<int> {
            queue<int> que;
            rep (i, n) {
                if (r[i]) que.push(i);
            }
            vector<int> deg(n);
            rep (i, n) deg[i] = g[i].size();
            while (!que.empty()) {
                int i = que.front(); que.pop();
                for (int j : rg[i]) {
                    if (r[j]) continue;
                    if (a[j] == f) {
                        r[j] = true;
                    }
                    else {
                        if ((--deg[j]) == 0) {
                            r[j] = true;
                        }
                    }
                    if (r[j]) que.push(j);
                }
            }
            return r;
        };
        auto r2 = calc(r, 1);
        if (count(all(r2), 1) == n) {
            rep (i, n) ans[ids[i]] = 1;
            break;
        }
        rep (i, n) r2[i] ^= 1;
        auto r3 = calc(r2, 0);
        vector<int> idx(n, -1);
        vector<int> ids2;
        int cnt = 0;
        rep (i, n) {
            if (!r3[i]) {
                idx[i] = cnt++;
                ids2.push_back(ids[i]);
            }
        }
        vector<int> a2(cnt), r4(cnt);
        rep (i, n) {
            if (idx[i] == -1) continue;
            a2[idx[i]] = a[i];
            r4[idx[i]] = r[i];
        }
        vector<int> u2, v2;
        rep (i, m) {
            if (idx[u[i]] == -1 || idx[v[i]] == -1) continue;
            u2.push_back(idx[u[i]]);
            v2.push_back(idx[v[i]]);
        }
        rep (i, n) {
            if (idx[i] == -1) ans[ids[i]] = 0;
        }

        a = a2;
        r = r4;
        u = u2;
        v = v2;
        ids = ids2;
    }
    return ans;
}

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