Submission #607461

#	Time	Username	Problem	Language	Result	Execution time	Memory
607461		yanndev	Toy Train (IOI17_train)	C++17	0 / 100	494 ms	1068 KiB

train

#include <bits/stdc++.h>
using namespace std;

const int MX = 5042;

int n;
int deg[MX];
bool vis[MX];
bool isOk[MX];
bool isAlice[MX];
bool isCharge[MX];
vector<int> rgraph[MX];

void BFS(int layer) {
    queue<int> nxt {};
    for (int i = 0; i < n; i++) {
        deg[i] = 0;
        if (isCharge[i] && vis[i])
            nxt.push(layer);
    }

    for (int i = 0; i < n; i++) {
        vis[i] = isOk[i] = false;
        for (auto& x: rgraph[i])
            deg[x]++;
    }
    
    while (!nxt.empty()) {
        auto cur = nxt.front();
        //cout << "cur is " << cur << '\n';
        nxt.pop();

        if (vis[cur])
            continue;
        vis[cur] = true;

        for (auto& x: rgraph[cur]) {
            if (!vis[x] && (--deg[x] == 0 || isAlice[x])) {
                isOk[x] = true;
                nxt.push(x);
            }
        }
    }
}

vector<int> who_wins(vector<int> a, vector<int> r, vector<int> u, vector<int> v) {
    n = (int)a.size();

    for (int i = 0; i < (int)u.size(); i++)
        rgraph[v[i]].push_back(u[i]);
    
    for (int i = 0; i < n; i++) {
        isAlice[i] = a[i];
        isCharge[i] = r[i];
    }

    for (int layer = 0; layer <= (int)r.size(); layer++)
        BFS(layer);

    vector<int> ans (n);
    for (int i = 0; i < n; i++)
        ans[i] = isOk[i];
    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