oj.uz

Submission #497784

# Submission time Handle Problem Language Result Execution time Memory
497784 2021-12-23T19:42:37 Z dxz05 Highway Tolls (IOI18_highway) C++14
100 / 100
 272 ms 12564 KB 
#include "highway.h"
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

#define all(x) (x).begin(), (x).end()

const int MAXN = 1e5 + 3e2;

int N;
vector<pair<int, int>> g[MAXN];

void bfs(int root, vector<int> &d, vector<int> &edges, vector<int> &p){
    queue<int> q;
    vector<bool> used(N, false);
    used[root] = true;
    q.push(root);
    d[root] = 0;
    p[root] = -1;

    while (!q.empty()){
        int x = q.front(); q.pop();
        for (auto e : g[x]){
            int y = e.first, i = e.second;
            if (!used[y]){
                used[y] = true;
                q.push(y);
                d[y] = d[x] + 1;
                p[y] = i;
                edges.push_back(i);
            }
        }
    }
}

vector<int> vec;

void find_pair(int _N, vector<int> U, vector<int> V, int A, int B) {
    N = _N;
    int M = U.size();

    for (int i = 0; i < M; i++){
        g[U[i]].emplace_back(V[i], i);
        g[V[i]].emplace_back(U[i], i);
    }

    vector<int> w(M, 0);

    ll onlyA = ask(w);

    int ind = 0;

    int l = 0, r = M - 1;
    while (l <= r){
        int mid = (l + r) >> 1;
        fill(all(w), 0);
        for (int i = 0; i <= mid; i++) w[i] = 1;
        ll res = ask(w);
        if (res != onlyA){
            ind = mid;
            r = mid - 1;
        } else l = mid + 1;
    }

    int u = U[ind], v = V[ind];

//    cerr << u << ' ' << v << endl;

    vector<int> du(N), dv(N), pu(N), pv(N);
    vector<int> eu, ev;

    bfs(u,  du, eu, pu);
    bfs(v,  dv, ev, pv);

    pu[u] = pv[v] = ind;

    for (int i = 0; i < g[U[ind]].size(); i++){
        if (g[U[ind]][i].first == V[ind]) g[U[ind]].erase(g[U[ind]].begin() + i);
    }
    for (int i = 0; i < g[V[ind]].size(); i++){
        if (g[V[ind]][i].first == U[ind]) g[V[ind]].erase(g[V[ind]].begin() + i);
    }

    vector<int> a, b;
    for (int i = 0; i < N; i++){
        if (du[i] < dv[i]) a.push_back(i);
        if (dv[i] < du[i]) b.push_back(i);
    }

    sort(all(a), [&](int i, int j){
        return du[i] < du[j];
    });

    sort(all(b), [&](int i, int j){
        return dv[i] < dv[j];
    });

//    cerr << endl;
//    for (int x : a) cerr << x << ' ' << pu[x] << endl; cerr << endl;
//    for (int x : b) cerr << x << ' ' << pv[x] << endl; cerr << endl;

    int S = -1, T = -1;

    l = 0, r = a.size() - 1;
    while (l <= r){
        int mid = (l + r) >> 1;

        fill(all(w), 1);
        w[ind] = 0;
        for (int i = 0; i <= mid; i++) w[pu[a[i]]] = 0;
        for (int i : b) w[pv[i]] = 0;

        if (ask(w) == onlyA){
            S = a[mid];
            r = mid - 1;
        } else l = mid + 1;
    }

    l = 0, r = b.size() - 1;
    while (l <= r){
        int mid = (l + r) >> 1;

        fill(all(w), 1);
        w[ind] = 0;
        for (int i = 0; i <= mid; i++) w[pv[b[i]]] = 0;
        for (int i : a) w[pu[i]] = 0;

//        cerr << "mid = " << mid << endl;
//        for (int x : w) cerr << x << ' '; cerr << endl << endl;

        if (ask(w) == onlyA){
            T = b[mid];
            r = mid - 1;
        } else l = mid + 1;
    }

//    cerr << S << ' ' << T << endl;

    answer(S, T);
}

Compilation message

highway.cpp: In function 'void find_pair(int, std::vector<int>, std::vector<int>, int, int)':
highway.cpp:79:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   79 |     for (int i = 0; i < g[U[ind]].size(); i++){
      |                     ~~^~~~~~~~~~~~~~~~~~
highway.cpp:82:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   82 |     for (int i = 0; i < g[V[ind]].size(); i++){
      |                     ~~^~~~~~~~~~~~~~~~~~

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2632 KB Output is correct
2 Correct 3 ms 2632 KB Output is correct
3 Correct 2 ms 2632 KB Output is correct
4 Correct 1 ms 2652 KB Output is correct
5 Correct 2 ms 2632 KB Output is correct
6 Correct 3 ms 2632 KB Output is correct
7 Correct 2 ms 2632 KB Output is correct
8 Correct 1 ms 2632 KB Output is correct
9 Correct 2 ms 2632 KB Output is correct
10 Correct 2 ms 2632 KB Output is correct
11 Correct 2 ms 2632 KB Output is correct
12 Correct 2 ms 2632 KB Output is correct

Subtask #2
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2632 KB Output is correct
2 Correct 12 ms 3600 KB Output is correct
3 Correct 168 ms 10600 KB Output is correct
4 Correct 137 ms 10692 KB Output is correct
5 Correct 176 ms 10616 KB Output is correct
6 Correct 191 ms 10668 KB Output is correct
7 Correct 136 ms 10684 KB Output is correct
8 Correct 166 ms 10700 KB Output is correct
9 Correct 163 ms 10688 KB Output is correct
10 Correct 139 ms 10656 KB Output is correct
11 Correct 187 ms 10120 KB Output is correct
12 Correct 176 ms 10264 KB Output is correct
13 Correct 145 ms 10156 KB Output is correct
14 Correct 148 ms 10036 KB Output is correct

Subtask #3
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 3528 KB Output is correct
2 Correct 29 ms 4196 KB Output is correct
3 Correct 48 ms 5120 KB Output is correct
4 Correct 112 ms 9968 KB Output is correct
5 Correct 101 ms 9964 KB Output is correct
6 Correct 110 ms 10260 KB Output is correct
7 Correct 137 ms 10152 KB Output is correct
8 Correct 114 ms 9968 KB Output is correct
9 Correct 111 ms 10060 KB Output is correct

Subtask #4
33.0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2708 KB Output is correct
2 Correct 18 ms 3572 KB Output is correct
3 Correct 91 ms 9100 KB Output is correct
4 Correct 156 ms 10644 KB Output is correct
5 Correct 125 ms 10672 KB Output is correct
6 Correct 163 ms 10672 KB Output is correct
7 Correct 134 ms 10728 KB Output is correct
8 Correct 138 ms 10720 KB Output is correct
9 Correct 189 ms 10672 KB Output is correct
10 Correct 143 ms 10656 KB Output is correct
11 Correct 191 ms 10112 KB Output is correct
12 Correct 161 ms 10036 KB Output is correct
13 Correct 218 ms 10160 KB Output is correct
14 Correct 173 ms 10120 KB Output is correct
15 Correct 108 ms 10692 KB Output is correct
16 Correct 107 ms 10756 KB Output is correct
17 Correct 212 ms 10108 KB Output is correct
18 Correct 191 ms 10036 KB Output is correct
19 Correct 105 ms 10688 KB Output is correct
20 Correct 207 ms 10032 KB Output is correct
21 Correct 123 ms 10976 KB Output is correct
22 Correct 138 ms 10972 KB Output is correct
23 Correct 118 ms 10932 KB Output is correct
24 Correct 170 ms 10736 KB Output is correct
25 Correct 187 ms 10176 KB Output is correct

Subtask #5
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 18 ms 3528 KB Output is correct
2 Correct 17 ms 3660 KB Output is correct
3 Correct 156 ms 11020 KB Output is correct
4 Correct 183 ms 11264 KB Output is correct
5 Correct 247 ms 12564 KB Output is correct
6 Correct 194 ms 12300 KB Output is correct
7 Correct 242 ms 12168 KB Output is correct
8 Correct 249 ms 12224 KB Output is correct
9 Correct 124 ms 9088 KB Output is correct
10 Correct 140 ms 9564 KB Output is correct
11 Correct 138 ms 10092 KB Output is correct
12 Correct 183 ms 11460 KB Output is correct
13 Correct 197 ms 11968 KB Output is correct
14 Correct 272 ms 12252 KB Output is correct
15 Correct 190 ms 12308 KB Output is correct
16 Correct 147 ms 10228 KB Output is correct
17 Correct 122 ms 10804 KB Output is correct
18 Correct 160 ms 11012 KB Output is correct
19 Correct 138 ms 10920 KB Output is correct
20 Correct 157 ms 11040 KB Output is correct
21 Correct 207 ms 12440 KB Output is correct

Subtask #6
31.0 / 31.0

# Verdict Execution time Memory Grader output
1 Correct 21 ms 3528 KB Output is correct
2 Correct 22 ms 3652 KB Output is correct
3 Correct 155 ms 11016 KB Output is correct
4 Correct 197 ms 11008 KB Output is correct
5 Correct 198 ms 11296 KB Output is correct
6 Correct 199 ms 12204 KB Output is correct
7 Correct 160 ms 11032 KB Output is correct
8 Correct 151 ms 11244 KB Output is correct
9 Correct 168 ms 11332 KB Output is correct
10 Correct 213 ms 12396 KB Output is correct
11 Correct 255 ms 12352 KB Output is correct
12 Correct 187 ms 12208 KB Output is correct
13 Correct 141 ms 10052 KB Output is correct
14 Correct 134 ms 9444 KB Output is correct
15 Correct 142 ms 10192 KB Output is correct
16 Correct 134 ms 9432 KB Output is correct
17 Correct 150 ms 10064 KB Output is correct
18 Correct 166 ms 9496 KB Output is correct
19 Correct 175 ms 11548 KB Output is correct
20 Correct 219 ms 11992 KB Output is correct
21 Correct 183 ms 12288 KB Output is correct
22 Correct 180 ms 12236 KB Output is correct
23 Correct 222 ms 12352 KB Output is correct
24 Correct 196 ms 12460 KB Output is correct
25 Correct 246 ms 12156 KB Output is correct
26 Correct 216 ms 12320 KB Output is correct
27 Correct 159 ms 10956 KB Output is correct
28 Correct 126 ms 10868 KB Output is correct
29 Correct 153 ms 11160 KB Output is correct
30 Correct 150 ms 11036 KB Output is correct
31 Correct 121 ms 10928 KB Output is correct
32 Correct 123 ms 10892 KB Output is correct
33 Correct 142 ms 11152 KB Output is correct
34 Correct 159 ms 10992 KB Output is correct
35 Correct 141 ms 10932 KB Output is correct
36 Correct 159 ms 10932 KB Output is correct
37 Correct 172 ms 11196 KB Output is correct
38 Correct 135 ms 10996 KB Output is correct
39 Correct 234 ms 12372 KB Output is correct
40 Correct 262 ms 12488 KB Output is correct
41 Correct 242 ms 12392 KB Output is correct
42 Correct 204 ms 12396 KB Output is correct