제출 #521212

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
521212		Jomnoi	Bitaro’s Party (JOI18_bitaro)	C++17	100 / 100	1504 ms	419632 KiB

bitaro

#include <bits/stdc++.h>
#define DEBUG 0
using namespace std;

const int N = 1e5 + 10;
const int M = 300;
const int INF = 1e9 + 7;

vector <int> rev[N];
vector <pair <int, int>> node[N];
stack <int> tmp;
bool notuse[N];
int dp[N];
int sz[N];

int solve(int u) {
    if(dp[u] != -1) {
        return dp[u];
    }

    dp[u] = -INF;
    for(auto v : rev[u]) {
        int x = solve(v);
        if(x != -INF) {
            dp[u] = max(dp[u], solve(v) + 1);
        }
    }

    if(notuse[u] == false) {
        dp[u] = max(dp[u], 0);
    }
    return dp[u];
}

int main() {
    cin.tie(0)->sync_with_stdio(0);
    int n, m, q;
    cin >> n >> m >> q;
    while(m--) {
        int s, e;
        cin >> s >> e;
        rev[e].push_back(s);
    }

    for(int u = 1; u <= n; u++) {
        for(auto v : rev[u]) {
            sz[v] = 0;
        }

        for(int i = 1; i <= M; i++) {
            pair <int, int> best = make_pair(-1, u);
            int idx = -1;
            for(auto v : rev[u]) {
                while(sz[v] < node[v].size() and notuse[node[v][sz[v]].second] == true) {
                    sz[v]++;
                }
                if(sz[v] < node[v].size() and best.first < node[v][sz[v]].first) {
                    best = node[v][sz[v]];
                    idx = v;
                }
            }
            node[u].emplace_back(best.first + 1, best.second);

            if(best.second == u) {
                break;
            }
            tmp.push(best.second);
            notuse[best.second] = true;
        }

        while(!tmp.empty()) {
            notuse[tmp.top()] = false;
            tmp.pop();
        }
    }

    if(DEBUG) {
        for(int i = 1; i <= n; i++) {
            for(auto [v, c] : node[i]) {
                cout << i << " : " << v << " " << c << endl;
            }
            cout << endl;
        }
    }

    while(q--) {
        int t, y;
        cin >> t >> y;
        int k = y;
        while(y--) {
            int c;
            cin >> c;
            notuse[c] = true;
            tmp.push(c);
        }

        int ans = -INF;
        if(k < M) {
            for(auto [v, c] : node[t]) {
                if(notuse[c] == false) {
                    ans = v;
                    break;
                }
            }
        }
        else {
            for(int i = 1; i <= t; i++) {
                dp[i] = -1;
            }
            ans = solve(t);
        }

        if(ans == -INF) {
            ans = -1;
        }
        cout << ans << '\n';

        while(!tmp.empty()) {
            notuse[tmp.top()] = false;
            tmp.pop();
        }
    }
    return 0;
}

컴파일 시 표준 에러 (stderr) 메시지

bitaro.cpp: In function 'int main()':
bitaro.cpp:54:29: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   54 |                 while(sz[v] < node[v].size() and notuse[node[v][sz[v]].second] == true) {
      |                       ~~~~~~^~~~~~~~~~~~~~~~
bitaro.cpp:57:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   57 |                 if(sz[v] < node[v].size() and best.first < node[v][sz[v]].first) {
      |                    ~~~~~~^~~~~~~~~~~~~~~~
bitaro.cpp:52:17: warning: variable 'idx' set but not used [-Wunused-but-set-variable]
   52 |             int idx = -1;
      |                 ^~~

• Subtask 1: 7 / 7
• Subtask 2: 7 / 7
• Subtask 3: 86 / 86