제출 #421459

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
421459		usachevd0	기지국 (IOI20_stations)	C++17	100 / 100	1178 ms	828 KiB

stations

#include <bits/stdc++.h>
#ifndef LOCAL
    #include "stations.h"
#endif

using namespace std;

#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define all(a) (a).begin(), (a).end()
#define Time (clock() * 1.0 / CLOCKS_PER_SEC)
using ll = long long;
using ull = unsigned long long;
using pii = pair<int, int>;
using pil = pair<int, ll>;
using pli = pair<ll, int>;
using pll = pair<ll, ll>;
using ld = long double;
template<typename T1, typename T2> bool chkmin(T1& x, T2 y) {
    return y < x ? (x = y, true) : false;
}
template<typename T1, typename T2> bool chkmax(T1& x, T2 y) {
    return y > x ? (x = y, true) : false;
}
void debug_out() {
    cerr << endl;
}
template<typename T1, typename... T2> void debug_out(T1 A, T2... B) {
    cerr << ' ' << A;
    debug_out(B...);
}
template<typename T> void mdebug_out(T* a, int n) {
    for (int i = 0; i < n; ++i)
        cerr << a[i] << ' ';
    cerr << endl;
}
#ifdef LOCAL
    #define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
    #define mdebug(a, n) cerr << #a << ": ", mdebug_out(a, n)
#else
    #define debug(...) 1337
    #define mdebug(a, n) 1337
#endif
template<typename T> ostream& operator << (ostream& stream, const vector<T>& v) {
    for (auto& e : v)
        stream << e << ' ';
    return stream;
}
template<typename T1, typename T2> ostream& operator << (ostream& stream, const pair<T1, T2>& p) {
    return stream << p.first << ' ' << p.second;
}

const int maxN = 1e3 + 3;
vector<int> G[maxN];
vector<int> ord;

void dfs(int v, int rev, int p = -1) {
    if (rev == 0) {
        ord.push_back(v);
        for (int u : G[v])
            if (u != p)
                dfs(u, 1, v);
    } else {
        for (int u : G[v])
            if (u != p)
                dfs(u, 0, v);
        ord.push_back(v);
    }
}


vector<int> label(int n, int __, vector<int> eu, vector<int> ev) {
    for (int v = 0; v < n; ++v) G[v].clear();
    for (int i = 0; i < n - 1; ++i) {
        int u = eu[i], v = ev[i];
        G[u].push_back(v);
        G[v].push_back(u);
    }
    ord.clear();
    dfs(0, 0);
    vector<int> pos(n);
    for (int i = 0; i < n; ++i)
        pos[ord[i]] = i;
    return pos;
}

int find_next_station(int s, int t, vector<int> g) {
    // debug(s, t, g);
    int rev;
    sort(all(g));
    if (s == 0 || s < g[0]) {
        int par = -1;
        if (s != 0) {
            par = g.back();
            g.pop_back();
        }
        if (!g.empty() && s < t && t <= g.back()) {
            return *lower_bound(all(g), t);
        } else return par;
    } else {
        int par = g[0];
        g.erase(g.begin());
        if (!g.empty() && g[0] <= t && t < s) {
            return *(upper_bound(all(g), t) - 1);
        } else return par;
    }
}

#ifdef LOCAL

static int max_label = 0;
static int r, n, k, q;
static std::vector<int> u, v, labels, answers;
static std::map<int, int> reverse_labels;
static std::vector<std::vector<int>> adjlist;
static int s, t, w;
static std::vector<int> c;

int main() {
    freopen("in", "r", stdin);
    assert(scanf("%d", &r) == 1);
    for (int tc = 0; tc < r; tc++) {
        assert(scanf("%d%d", &n, &k) == 2);
        u.resize(n - 1);
        v.resize(n - 1);
        adjlist.clear();
        adjlist.resize(n);
        for (int i = 0; i < n - 1; i++) {
            assert(scanf("%d%d", &u[i], &v[i]) == 2);
            adjlist[u[i]].push_back(v[i]);
            adjlist[v[i]].push_back(u[i]);
        }
        labels = label(n, k, u, v);
        debug(labels);
        if ((int)labels.size() != n) {
            printf("Number of labels not equal to %d\n", n);
            exit(0);
        }
        reverse_labels.clear();
        for (int i = 0; i < n; i++) {
            if (labels[i] < 0 || labels[i] > k) {
                printf("Label not in range 0 to %d\n", k);
                exit(0);
            }
            if (reverse_labels.find(labels[i]) != reverse_labels.end()) {
                printf("Labels not unique\n");
                exit(0);
            }
            reverse_labels[labels[i]] = i;
            if (labels[i] > max_label) {
                max_label = labels[i];
            }
        }
        assert(scanf("%d", &q) == 1);
        for (int i = 0; i < q; i++) {
            assert(scanf("%d%d%d", &s, &t, &w) == 3);
            c.clear();
            for (int v : adjlist[s]) {
                c.push_back(labels[v]);
            }
            std::sort(c.begin(), c.end());
            int answer = find_next_station(labels[s], labels[t], c);
            if (!std::binary_search(c.begin(), c.end(), answer)) {
                printf("Label %d returned by find_next_station not found in c\n", answer);
                exit(0);
            }
            answers.push_back(reverse_labels[answer]);
        }
    }
    printf("%d\n", max_label);
    for (int index : answers) {
        printf("%d\n", index);
    }
    exit(0);
}


// int32_t main() {
//     #ifdef LOCAL
//         freopen("in", "r", stdin);
//     #endif
//     ios::sync_with_stdio(0);
//     cin.tie(0);
    
    
    
    
//     return 0;
// }
#endif

컴파일 시 표준 에러 (stderr) 메시지

stations.cpp: In function 'int find_next_station(int, int, std::vector<int>)':
stations.cpp:91:9: warning: unused variable 'rev' [-Wunused-variable]
   91 |     int rev;
      |         ^~~

• Subtask 1: 5 / 5
• Subtask 2: 8 / 8
• Subtask 3: 16 / 16
• Subtask 4: 10 / 10
• Subtask 5: 61 / 61