Submission #564457

# Submission time Handle Problem Language Result Execution time Memory
564457 2022-05-19T09:07:31 Z hoanghq2004 Portals (BOI14_portals) C++14
100 / 100
354 ms 46552 KB
#include <bits/stdc++.h>

using namespace std;

int n, m;
char c[1010][1010];
pair <int, int> nxt[1010][1010][4], s, t;
int mx[4] = {-1, 0, 1, 0};
int my[4] = {0, -1, 0, 1};
int d[1010][1010];
int dist_to_wall[1010][1010];

void bfs() {
    queue <pair <int, int> > q;
    for (int i = 0; i <= n + 1; ++i)
        for (int j = 0; j <= m + 1; ++j)
            if (c[i][j] == '#') {
                dist_to_wall[i][j] = 0;
                q.push({i, j});
            }
            else dist_to_wall[i][j] = 1e9;
    while (!q.empty()) {
        int u = q.front().first;
        int v = q.front().second;
        q.pop();
        for (int i = 0; i < 4; ++i) {
            int x = u + mx[i], y = v + my[i];
            if (x < 0 || x > n + 1 || y < 0 || y > m + 1 || dist_to_wall[x][y] != 1e9) continue;
            dist_to_wall[x][y] = dist_to_wall[u][v] + 1;
            q.push({x, y});
        }
    }
}

void dijkstra() {
    priority_queue <pair <int, pair <int, int> > > pq;
    for (int i = 0; i <= n + 1; ++i)
        for (int j = 0; j <= m + 1; ++j)
            d[i][j] = 1e9;
    d[s.first][s.second] = 0;
    pq.push({0, s});
    while (!pq.empty()) {
        int u = pq.top().second.first;
        int v = pq.top().second.second;
        int dist = - pq.top().first;
        pq.pop();
        if (dist != d[u][v]) continue;
        for (int i = 0; i < 4; ++i) {
            int x = u + mx[i];
            int y = v + my[i];
            if (c[x][y] != '#' && d[x][y] > d[u][v] + 1) {
                d[x][y] = d[u][v] + 1;
                pq.push({- d[x][y], {x, y}});
            }
            x = nxt[u][v][i].first, y = nxt[u][v][i].second;
            if (d[u][v] + dist_to_wall[u][v] < d[x][y]) {
                d[x][y] = d[u][v] + dist_to_wall[u][v];
                pq.push({- d[x][y], {x, y}});
            }
        }
    }
}

int main() {
    scanf("%d%d", &n, &m);
    for (int i = 0; i <= n + 1; ++i)
        for (int j = 0; j <= m + 1; ++j)
            c[i][j] = '#';
    for (int i = 1; i <= n; ++i)
        for (int j = 1; j <= m; ++j)
            scanf(" %c", &c[i][j]);

    for (int i = 1; i <= n; ++i)
        for (int j = 1; j <= m; ++j) {
            if (c[i][j] == 'S') s = {i, j};
            if (c[i][j] == 'C') t = {i, j};
        }
    for (int i = 1; i <= n; ++i)
        for (int j = 1; j <= m; ++j) {
            if (c[i - 1][j] == '#') nxt[i][j][2] = {i, j};
            else nxt[i][j][2] = nxt[i - 1][j][2];
            if (c[i][j - 1] == '#') nxt[i][j][3] = {i, j};
            else nxt[i][j][3] = nxt[i][j - 1][3];
        }
    for (int i = n; i >= 1; --i)
        for (int j = m; j >= 1; --j) {
            if (c[i + 1][j] == '#') nxt[i][j][0] = {i, j};
            else nxt[i][j][0] = nxt[i + 1][j][0];
            if (c[i][j + 1] == '#') nxt[i][j][1] = {i, j};
            else nxt[i][j][1] = nxt[i][j + 1][1];
        }
    bfs();
    dijkstra();
    cout << d[t.first][t.second];
}

Compilation message

portals.cpp: In function 'int main()':
portals.cpp:65:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   65 |     scanf("%d%d", &n, &m);
      |     ~~~~~^~~~~~~~~~~~~~~~
portals.cpp:71:18: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   71 |             scanf(" %c", &c[i][j]);
      |             ~~~~~^~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 468 KB Output is correct
3 Correct 1 ms 436 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 436 KB Output is correct
6 Correct 0 ms 468 KB Output is correct
7 Correct 1 ms 468 KB Output is correct
8 Correct 1 ms 468 KB Output is correct
9 Correct 0 ms 340 KB Output is correct
10 Correct 1 ms 340 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 432 KB Output is correct
3 Correct 1 ms 432 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 468 KB Output is correct
6 Correct 1 ms 436 KB Output is correct
7 Correct 1 ms 468 KB Output is correct
8 Correct 1 ms 428 KB Output is correct
9 Correct 1 ms 980 KB Output is correct
10 Correct 1 ms 944 KB Output is correct
11 Correct 1 ms 944 KB Output is correct
12 Correct 2 ms 980 KB Output is correct
13 Correct 2 ms 980 KB Output is correct
14 Correct 1 ms 340 KB Output is correct
15 Correct 1 ms 980 KB Output is correct
16 Correct 1 ms 340 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 468 KB Output is correct
3 Correct 1 ms 432 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 8 ms 4380 KB Output is correct
6 Correct 12 ms 4308 KB Output is correct
7 Correct 10 ms 4308 KB Output is correct
8 Correct 5 ms 4384 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 1 ms 468 KB Output is correct
3 Correct 1 ms 436 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 436 KB Output is correct
6 Correct 1 ms 436 KB Output is correct
7 Correct 1 ms 436 KB Output is correct
8 Correct 1 ms 468 KB Output is correct
9 Correct 2 ms 980 KB Output is correct
10 Correct 1 ms 948 KB Output is correct
11 Correct 1 ms 980 KB Output is correct
12 Correct 1 ms 948 KB Output is correct
13 Correct 1 ms 980 KB Output is correct
14 Correct 8 ms 4308 KB Output is correct
15 Correct 9 ms 4384 KB Output is correct
16 Correct 9 ms 4424 KB Output is correct
17 Correct 9 ms 4256 KB Output is correct
18 Correct 10 ms 4308 KB Output is correct
19 Correct 11 ms 4180 KB Output is correct
20 Correct 11 ms 4188 KB Output is correct
21 Correct 9 ms 4284 KB Output is correct
22 Correct 9 ms 4296 KB Output is correct
23 Correct 11 ms 4360 KB Output is correct
24 Correct 10 ms 4156 KB Output is correct
25 Correct 1 ms 340 KB Output is correct
26 Correct 1 ms 944 KB Output is correct
27 Correct 1 ms 340 KB Output is correct
28 Correct 6 ms 4308 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 0 ms 468 KB Output is correct
3 Correct 1 ms 468 KB Output is correct
4 Correct 0 ms 340 KB Output is correct
5 Correct 1 ms 468 KB Output is correct
6 Correct 1 ms 468 KB Output is correct
7 Correct 1 ms 432 KB Output is correct
8 Correct 1 ms 436 KB Output is correct
9 Correct 1 ms 980 KB Output is correct
10 Correct 2 ms 980 KB Output is correct
11 Correct 1 ms 952 KB Output is correct
12 Correct 1 ms 980 KB Output is correct
13 Correct 1 ms 944 KB Output is correct
14 Correct 7 ms 4308 KB Output is correct
15 Correct 9 ms 4288 KB Output is correct
16 Correct 9 ms 4308 KB Output is correct
17 Correct 9 ms 4252 KB Output is correct
18 Correct 11 ms 4308 KB Output is correct
19 Correct 11 ms 4224 KB Output is correct
20 Correct 11 ms 4252 KB Output is correct
21 Correct 9 ms 4308 KB Output is correct
22 Correct 9 ms 4400 KB Output is correct
23 Correct 9 ms 4320 KB Output is correct
24 Correct 213 ms 44604 KB Output is correct
25 Correct 354 ms 42136 KB Output is correct
26 Correct 292 ms 42068 KB Output is correct
27 Correct 281 ms 41968 KB Output is correct
28 Correct 176 ms 45508 KB Output is correct
29 Correct 203 ms 46552 KB Output is correct
30 Correct 219 ms 46472 KB Output is correct
31 Correct 8 ms 4160 KB Output is correct
32 Correct 255 ms 41812 KB Output is correct
33 Correct 1 ms 304 KB Output is correct
34 Correct 1 ms 980 KB Output is correct
35 Correct 202 ms 43900 KB Output is correct
36 Correct 1 ms 340 KB Output is correct
37 Correct 6 ms 4416 KB Output is correct
38 Correct 141 ms 44732 KB Output is correct
39 Correct 166 ms 45788 KB Output is correct