#include <bits/stdc++.h>
using namespace std;
const int inf = 2e3 + 9;
const int dx[4] = {-1, 1, 0, 0};
const int dy[4] = {0, 0, -1, 1};
struct ds {
int par[inf * inf], siz[inf * inf];
inline int find(int u) {
if (u == par[u]) return u;
return par[u] = find(par[u]);
}
inline void merge(int u, int v) {
u = find(u); v = find(v);
if (u == v) return;
par[u] = v;
siz[v] += siz[u];
siz[u] = 0;
}
} cul;
int n, m;
int vis[inf][inf];
int main() {
scanf("%d%d", &n, &m);
for (int i = 0; i < n * n; ++i) cul.par[i] = i;
memset(vis, -1, sizeof(vis));
queue<pair<int, pair<int, int>>> q;
for (int i = 0; i < m; i++) {
int x, y; scanf("%d%d", &x, &y);
cul.siz[--y * n + --x] = 1;
q.push(make_pair(0, make_pair(y, x)));
vis[y][x] = y * n + x;
}
while (!q.empty()) {
int dist = q.front().first;
int y = q.front().second.first, x = q.front().second.second;
int here = y * n + x;
q.pop();
cul.merge(here, vis[y][x]);
for (int i = 0; i < 4; ++i) {
int ny = y + dy[i], nx = x + dx[i];
if (ny < 0 || ny >= n || nx < 0 || nx >= n) continue;
int there = ny * n + nx;
if (cul.siz[cul.find(there)] && cul.siz[cul.find(here)]) cul.merge(there, here);
if (vis[ny][nx] == -1) {
q.push(make_pair(dist + 1, make_pair(ny, nx)));
vis[ny][nx] = here;
}
}
if (cul.siz[cul.find(here)] == m) {
printf("%d\n", dist);
break;
}
}
}
Compilation message
civilization.cpp: In function 'int main()':
civilization.cpp:28:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d%d", &n, &m);
~~~~~^~~~~~~~~~~~~~~~
civilization.cpp:33:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
int x, y; scanf("%d%d", &x, &y);
~~~~~^~~~~~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
16 ms |
16248 KB |
Output is correct |
2 |
Correct |
15 ms |
16248 KB |
Output is correct |
3 |
Correct |
16 ms |
16248 KB |
Output is correct |
4 |
Correct |
16 ms |
16248 KB |
Output is correct |
5 |
Correct |
16 ms |
16248 KB |
Output is correct |
6 |
Correct |
16 ms |
16248 KB |
Output is correct |
7 |
Correct |
16 ms |
16248 KB |
Output is correct |
8 |
Correct |
16 ms |
16248 KB |
Output is correct |
9 |
Correct |
16 ms |
16248 KB |
Output is correct |
10 |
Correct |
15 ms |
16248 KB |
Output is correct |
11 |
Correct |
16 ms |
16168 KB |
Output is correct |
12 |
Correct |
19 ms |
16276 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
16 ms |
16248 KB |
Output is correct |
2 |
Correct |
15 ms |
16248 KB |
Output is correct |
3 |
Correct |
16 ms |
16248 KB |
Output is correct |
4 |
Correct |
16 ms |
16248 KB |
Output is correct |
5 |
Correct |
16 ms |
16248 KB |
Output is correct |
6 |
Correct |
16 ms |
16248 KB |
Output is correct |
7 |
Correct |
16 ms |
16248 KB |
Output is correct |
8 |
Correct |
16 ms |
16248 KB |
Output is correct |
9 |
Correct |
16 ms |
16248 KB |
Output is correct |
10 |
Correct |
15 ms |
16248 KB |
Output is correct |
11 |
Correct |
16 ms |
16168 KB |
Output is correct |
12 |
Correct |
121 ms |
24088 KB |
Output is correct |
13 |
Correct |
87 ms |
24056 KB |
Output is correct |
14 |
Correct |
124 ms |
24016 KB |
Output is correct |
15 |
Correct |
90 ms |
24016 KB |
Output is correct |
16 |
Correct |
30 ms |
22520 KB |
Output is correct |
17 |
Correct |
262 ms |
28136 KB |
Output is correct |
18 |
Correct |
292 ms |
28152 KB |
Output is correct |
19 |
Correct |
303 ms |
28216 KB |
Output is correct |
20 |
Correct |
312 ms |
28152 KB |
Output is correct |
21 |
Correct |
284 ms |
28124 KB |
Output is correct |
22 |
Correct |
22 ms |
23932 KB |
Output is correct |
23 |
Correct |
133 ms |
24056 KB |
Output is correct |
24 |
Correct |
19 ms |
16276 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
16 ms |
16248 KB |
Output is correct |
2 |
Correct |
15 ms |
16248 KB |
Output is correct |
3 |
Correct |
16 ms |
16248 KB |
Output is correct |
4 |
Correct |
16 ms |
16248 KB |
Output is correct |
5 |
Correct |
16 ms |
16248 KB |
Output is correct |
6 |
Correct |
16 ms |
16248 KB |
Output is correct |
7 |
Correct |
16 ms |
16248 KB |
Output is correct |
8 |
Correct |
16 ms |
16248 KB |
Output is correct |
9 |
Correct |
16 ms |
16248 KB |
Output is correct |
10 |
Correct |
15 ms |
16248 KB |
Output is correct |
11 |
Correct |
16 ms |
16168 KB |
Output is correct |
12 |
Correct |
121 ms |
24088 KB |
Output is correct |
13 |
Correct |
87 ms |
24056 KB |
Output is correct |
14 |
Correct |
124 ms |
24016 KB |
Output is correct |
15 |
Correct |
90 ms |
24016 KB |
Output is correct |
16 |
Correct |
30 ms |
22520 KB |
Output is correct |
17 |
Correct |
262 ms |
28136 KB |
Output is correct |
18 |
Correct |
292 ms |
28152 KB |
Output is correct |
19 |
Correct |
303 ms |
28216 KB |
Output is correct |
20 |
Correct |
312 ms |
28152 KB |
Output is correct |
21 |
Correct |
284 ms |
28124 KB |
Output is correct |
22 |
Correct |
22 ms |
23932 KB |
Output is correct |
23 |
Correct |
133 ms |
24056 KB |
Output is correct |
24 |
Correct |
323 ms |
45432 KB |
Output is correct |
25 |
Correct |
407 ms |
47468 KB |
Output is correct |
26 |
Correct |
281 ms |
46584 KB |
Output is correct |
27 |
Correct |
312 ms |
45576 KB |
Output is correct |
28 |
Correct |
227 ms |
45272 KB |
Output is correct |
29 |
Execution timed out |
1031 ms |
54084 KB |
Time limit exceeded |
30 |
Halted |
0 ms |
0 KB |
- |