oj.uz

답안 #156072

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
156072 2019-10-03T07:30:57 Z atoiz 물병 (JOI14_bottle) C++14
30 / 100
 699 ms 72884 KB 
#include <iostream>
#include <algorithm>
#include <vector>
#include <cassert>

using namespace std;

const int MAXN = 200007, MAXH = 2007, LOG = 18;
const int DX[4] = {-1, 1, 0, 0}, DY[4] = {0, 0, -1, 1};
vector<pair<int, int>> gr[MAXN];
int h, w, p, q;
int col[MAXH][MAXH], dis[MAXH][MAXH];
int anc[LOG][MAXN], up[LOG][MAXN], dep[MAXN];
string str[MAXH];
int a[MAXN], b[MAXN];

int dsu[MAXN], sz[MAXN];
void init(int n) { for (int i = 0; i < n; ++i) dsu[i] = i, sz[i] = 1; }
int get(int i) { return (i == dsu[i] ? i : dsu[i] = get(dsu[i])); }
bool same(int i, int j) { return get(i) == get(j); }
void join(int i, int j) { i = get(i), j = get(j); if (i == j) return; if (sz[i] < sz[j]) swap(i, j); sz[i] += sz[j], dsu[j] = i; }

bool is_valid(int i, int j) { return i >= 0 && i < h && j >= 0 && j < w && str[i][j] != '#'; }

int qu_x[MAXH * MAXH], qu_y[MAXH * MAXH], fr, rr;

void add_edge(int u, int v, int w)
{
    if (same(u, v)) return;
    join(u, v);
    gr[u].emplace_back(w, v);
    gr[v].emplace_back(w, u);
}

void dfs(int u)
{
    for (auto a : gr[u]) if (a.second != anc[0][u]) {
        dep[a.second] = dep[u] + 1;
        anc[0][a.second] = u;
        up[0][a.second] = a.first;
        dfs(a.second);
    }
}

int max_path(int u, int v)
{
    if (!same(u, v)) return -1;
    int ans = 0;
    if (dep[u] < dep[v]) swap(u, v);
    for (int i = LOG - 1; i >= 0; --i) if (dep[u] - (1 << i) >= dep[v]) ans = max(ans, up[i][u]), u = anc[i][u];
    assert(dep[u] == dep[v]);
    if (u == v) return ans;
    for (int i = LOG - 1; i >= 0; --i) if (anc[i][u] != anc[i][v]) ans = max(ans, max(up[i][u], up[i][v])), u = anc[i][u], v = anc[i][v];
    assert(anc[0][u] == anc[0][v]);
    return max(ans, max(up[0][u], up[0][v]));
}

int main()
{
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    cin >> h >> w >> p >> q;
    for (int i = 0; i < h; ++i) cin >> str[i];
    for (int i = 1; i <= p; ++i) {
        cin >> a[i] >> b[i];
        col[--a[i]][--b[i]] = i;
        qu_x[rr] = a[i], qu_y[rr] = b[i]; ++rr;
    }

    init(p + 1);
    while (fr < rr) {
        int x = qu_x[fr], y = qu_y[fr]; ++fr;
        for (int d = 0; d < 4; ++d) {
            int x0 = x + DX[d], y0 = y + DY[d];
            if (!is_valid(x0, y0)) continue;
            if (col[x0][y0]) add_edge(col[x0][y0], col[x][y], dis[x0][y0] + dis[x][y]);
            else {
                col[x0][y0] = col[x][y];
                dis[x0][y0] = dis[x][y] + 1;
                qu_x[rr] = x0, qu_y[rr] = y0; ++rr;
            }
        }
    }

    for (int u = 1; u <= p; ++u) if (!anc[0][u]) dfs(u);
    for (int lg = 1; lg < LOG; ++lg) for (int u = 1; u <= p; ++u) {
        up[lg][u] = max(up[lg - 1][u], up[lg - 1][anc[lg - 1][u]]);
        anc[lg][u] = anc[lg - 1][anc[lg - 1][u]];
    }

    for (int i = 0; i < q; ++i) {
        int u, v;
        cin >> u >> v;
        cout << max_path(u, v) << '\n';
    }
}

Subtask #1
0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 8 ms 6008 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #2
30.0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 41 ms 24440 KB Output is correct
2 Correct 43 ms 12028 KB Output is correct
3 Correct 333 ms 57592 KB Output is correct
4 Correct 641 ms 63100 KB Output is correct
5 Correct 646 ms 67048 KB Output is correct
6 Correct 359 ms 57336 KB Output is correct
7 Correct 545 ms 63288 KB Output is correct
8 Correct 626 ms 66884 KB Output is correct
9 Correct 699 ms 72884 KB Output is correct
10 Correct 373 ms 62316 KB Output is correct
11 Correct 478 ms 62524 KB Output is correct
12 Correct 155 ms 52208 KB Output is correct
13 Correct 245 ms 52472 KB Output is correct
14 Correct 146 ms 52384 KB Output is correct
15 Correct 253 ms 52372 KB Output is correct

Subtask #3
0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 46 ms 24364 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 487 ms 59240 KB Output isn't correct
2 Halted 0 ms 0 KB -