#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int, int>;
#define FOR(i, a, b) for (int i = a; i < (b); i++)
#define F0R(i, a) for (int i = 0; i < (a); i++)
#define F0R1(i, a) for (int i = 1; i <= (a); i++)
#define FORd(i, a, b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i, a) for (int i = (a)-1; i >= 0; i--)
#define F0Rd1(i, a) for (int i = a; i > 0; i--)
#define SORT(vec) sort(vec.begin(), vec.end())
#define S0RT(arr, n) sort(arr, arr + n)
#define pA first
#define pB second
#define MOD 1000000007
#define nl "\n"
#define pb push_back
int n, steps, rootX, rootY, homeX, homeY;
vector<pii> adj[800][800];
bool vis[800][800];
bool visBee[800][800];
set<pii> updateQueue;
bool blocked[800][800];
vector<pii> hives;
queue<pii> beeQueue;
int initialDist = 0;
void moveBees() {
int sz = beeQueue.size();
FOR(i, 0, sz) {
pii node = beeQueue.front();
beeQueue.pop();
for (pii neighbor : adj[node.pA][node.pB]) {
if (!visBee[neighbor.pA][neighbor.pB] && !(neighbor.pA == homeX && neighbor.pB == homeY)) {
visBee[neighbor.pA][neighbor.pB] = true;
// updateQueue.insert(neighbor);
beeQueue.push(neighbor);
}
}
}
}
bool bfs(int eatHoney) {
FOR(i, 0, n) {
FOR(j, 0, n) {
vis[i][j] = false;
visBee[i][j] = false;
}
}
queue<pii> bfsQueue;
beeQueue = queue<pii>();
vis[rootX][rootY] = true;
bfsQueue.push(pii(rootX, rootY));
for (pii i : hives) {
visBee[i.pA][i.pB] = true;
beeQueue.push(i);
}
FOR(i, 0, eatHoney) { moveBees(); }
// somehow avoid having to replace the queue with every step
while (!bfsQueue.empty()) {
FOR(i, 0, steps) {
if (i == steps - 1) {
moveBees();
}
int sz = bfsQueue.size();
FOR(j, 0, sz) {
pii node = bfsQueue.front();
bfsQueue.pop();
for (pii neighbor : adj[node.pA][node.pB]) {
if (!vis[neighbor.pA][neighbor.pB] && (!visBee[neighbor.pA][neighbor.pB])) { // make sure the visbee was done not in the previous round or that i == sz - 1
vis[neighbor.pA][neighbor.pB] = true;
if (neighbor.pA == homeX && neighbor.pB == homeY) {
return true;
}
bfsQueue.push(neighbor);
}
}
}
}
}
return false;
}
void gridAdj() {
for (int i = 0; i < n; i++) {
for (int j = 0; j < n; j++) {
if (!blocked[i][j]) {
if (i > 0 && !blocked[i - 1][j]) {
adj[i][j].pb(pii(i - 1, j));
}
if (i < n - 1 && !blocked[i + 1][j]) {
adj[i][j].pb(pii(i + 1, j));
}
if (j > 0 && !blocked[i][j - 1]) {
adj[i][j].pb(pii(i, j - 1));
}
if (j < n - 1 && !blocked[i][j + 1]) {
adj[i][j].pb(pii(i, j + 1));
}
}
}
}
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cin >> n >> steps;
for (int i = 0; i < n; i++) {
string s;
cin >> s;
FOR(j, 0, n) {
if (s[j] == 'T') {
blocked[i][j] = true;
} else if (s[j] == 'M') {
rootX = i;
rootY = j;
} else if (s[j] == 'D') {
homeX = i;
homeY = j;
} else if (s[j] == 'H') {
hives.pb(pii(i, j));
}
}
}
gridAdj();
int l = 0;
int r = 1e6;
int ans = l - 1;
while (l <= r) {
ll mid = (r + l) / 2;
if (bfs(mid)) {
ans = mid;
l = mid + 1;
} else {
r = mid - 1;
}
}
cout << ans << nl;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
12 ms |
15308 KB |
Output is correct |
2 |
Correct |
13 ms |
15356 KB |
Output is correct |
3 |
Correct |
11 ms |
15352 KB |
Output is correct |
4 |
Correct |
12 ms |
15308 KB |
Output is correct |
5 |
Correct |
12 ms |
15356 KB |
Output is correct |
6 |
Correct |
12 ms |
15368 KB |
Output is correct |
7 |
Execution timed out |
1057 ms |
47924 KB |
Time limit exceeded |
8 |
Correct |
17 ms |
15308 KB |
Output is correct |
9 |
Correct |
12 ms |
15356 KB |
Output is correct |
10 |
Correct |
12 ms |
15352 KB |
Output is correct |
11 |
Correct |
12 ms |
15300 KB |
Output is correct |
12 |
Incorrect |
111 ms |
15484 KB |
Output isn't correct |
13 |
Incorrect |
15 ms |
15516 KB |
Output isn't correct |
14 |
Correct |
15 ms |
15612 KB |
Output is correct |
15 |
Correct |
14 ms |
15416 KB |
Output is correct |
16 |
Correct |
14 ms |
15416 KB |
Output is correct |
17 |
Correct |
13 ms |
15356 KB |
Output is correct |
18 |
Correct |
14 ms |
15356 KB |
Output is correct |
19 |
Correct |
12 ms |
15352 KB |
Output is correct |
20 |
Correct |
13 ms |
15344 KB |
Output is correct |
21 |
Correct |
15 ms |
15388 KB |
Output is correct |
22 |
Correct |
16 ms |
15436 KB |
Output is correct |
23 |
Correct |
15 ms |
15516 KB |
Output is correct |
24 |
Correct |
15 ms |
15484 KB |
Output is correct |
25 |
Correct |
13 ms |
15488 KB |
Output is correct |
26 |
Correct |
17 ms |
15484 KB |
Output is correct |
27 |
Correct |
15 ms |
15588 KB |
Output is correct |
28 |
Correct |
14 ms |
15484 KB |
Output is correct |
29 |
Correct |
13 ms |
15564 KB |
Output is correct |
30 |
Correct |
15 ms |
15616 KB |
Output is correct |
31 |
Correct |
18 ms |
15612 KB |
Output is correct |
32 |
Correct |
13 ms |
15564 KB |
Output is correct |
33 |
Correct |
41 ms |
18204 KB |
Output is correct |
34 |
Correct |
40 ms |
18204 KB |
Output is correct |
35 |
Correct |
116 ms |
20084 KB |
Output is correct |
36 |
Correct |
49 ms |
18908 KB |
Output is correct |
37 |
Correct |
48 ms |
18944 KB |
Output is correct |
38 |
Correct |
209 ms |
21416 KB |
Output is correct |
39 |
Correct |
58 ms |
19792 KB |
Output is correct |
40 |
Correct |
58 ms |
19776 KB |
Output is correct |
41 |
Correct |
256 ms |
22896 KB |
Output is correct |
42 |
Correct |
66 ms |
20600 KB |
Output is correct |
43 |
Correct |
74 ms |
20692 KB |
Output is correct |
44 |
Correct |
345 ms |
24508 KB |
Output is correct |
45 |
Correct |
81 ms |
21692 KB |
Output is correct |
46 |
Correct |
82 ms |
21640 KB |
Output is correct |
47 |
Correct |
405 ms |
26368 KB |
Output is correct |
48 |
Correct |
91 ms |
22732 KB |
Output is correct |
49 |
Correct |
95 ms |
22752 KB |
Output is correct |
50 |
Correct |
521 ms |
28344 KB |
Output is correct |
51 |
Correct |
107 ms |
23932 KB |
Output is correct |
52 |
Correct |
102 ms |
23800 KB |
Output is correct |
53 |
Correct |
605 ms |
30468 KB |
Output is correct |
54 |
Correct |
118 ms |
25156 KB |
Output is correct |
55 |
Correct |
120 ms |
25084 KB |
Output is correct |
56 |
Correct |
717 ms |
32760 KB |
Output is correct |
57 |
Correct |
142 ms |
26448 KB |
Output is correct |
58 |
Correct |
143 ms |
26416 KB |
Output is correct |
59 |
Correct |
842 ms |
35216 KB |
Output is correct |
60 |
Correct |
152 ms |
27776 KB |
Output is correct |
61 |
Correct |
166 ms |
27876 KB |
Output is correct |
62 |
Correct |
956 ms |
37820 KB |
Output is correct |
63 |
Correct |
573 ms |
31520 KB |
Output is correct |
64 |
Correct |
554 ms |
31324 KB |
Output is correct |
65 |
Correct |
559 ms |
31388 KB |
Output is correct |
66 |
Correct |
650 ms |
31392 KB |
Output is correct |
67 |
Correct |
561 ms |
31392 KB |
Output is correct |
68 |
Correct |
709 ms |
31428 KB |
Output is correct |
69 |
Correct |
681 ms |
31424 KB |
Output is correct |
70 |
Correct |
690 ms |
31428 KB |
Output is correct |
71 |
Correct |
676 ms |
31428 KB |
Output is correct |
72 |
Incorrect |
793 ms |
31428 KB |
Output isn't correct |
73 |
Execution timed out |
1058 ms |
47920 KB |
Time limit exceeded |
74 |
Execution timed out |
1018 ms |
47796 KB |
Time limit exceeded |
75 |
Execution timed out |
1053 ms |
47812 KB |
Time limit exceeded |
76 |
Execution timed out |
1074 ms |
47812 KB |
Time limit exceeded |
77 |
Execution timed out |
1057 ms |
47904 KB |
Time limit exceeded |
78 |
Execution timed out |
1061 ms |
47844 KB |
Time limit exceeded |
79 |
Execution timed out |
1057 ms |
47900 KB |
Time limit exceeded |
80 |
Execution timed out |
1036 ms |
47896 KB |
Time limit exceeded |
81 |
Execution timed out |
1069 ms |
47932 KB |
Time limit exceeded |
82 |
Execution timed out |
1047 ms |
47892 KB |
Time limit exceeded |
83 |
Execution timed out |
1047 ms |
47716 KB |
Time limit exceeded |
84 |
Execution timed out |
1026 ms |
47684 KB |
Time limit exceeded |
85 |
Execution timed out |
1087 ms |
47684 KB |
Time limit exceeded |
86 |
Execution timed out |
1041 ms |
47684 KB |
Time limit exceeded |
87 |
Execution timed out |
1073 ms |
47708 KB |
Time limit exceeded |
88 |
Execution timed out |
1065 ms |
47808 KB |
Time limit exceeded |
89 |
Execution timed out |
1090 ms |
47728 KB |
Time limit exceeded |
90 |
Execution timed out |
1060 ms |
47700 KB |
Time limit exceeded |
91 |
Execution timed out |
1089 ms |
47804 KB |
Time limit exceeded |
92 |
Execution timed out |
1070 ms |
47828 KB |
Time limit exceeded |