#include <bits/stdc++.h>
using namespace std;
#define int long long
#define forinc(i,a,b) for(int i=a;i<=b;++i)
#define fordec(i,a,b) for(int i=a;i>=b;--i)
#define pb push_back
#define pii pair <int,int>
#define fi first
#define se second
#define all(x) x.begin(), x.end()
const int N = 802, inf = 1e14;
const int H[] = {1, 0, -1, 0};
const int C[] = {0, 1, 0, -1};
int n, s;
char a[N][N];
int t[N][N];
bool cx[N][N];
pii sta, fin;
bool valid (const int& x, const int& y)
{
return x > 0 && y > 0 && x <= n && y <= n && a[x][y] != 'T';
}
struct adt {int x, y, st;};
bool ok (const int& tg)
{
queue <adt> q;
memset(cx, 0, sizeof cx);
q.push({sta.fi, sta.se, 0});
cx[sta.fi][sta.se] = 1;
while(q.size()) {
auto tmp = q.front(); q.pop();
if(tmp.x == fin.fi && tmp.y == fin.se) return 1;
forinc(i,0,3) {
int nh = tmp.x + H[i];
int nc = tmp.y + C[i];
if(valid(nh, nc) && !cx[nh][nc] && (tmp.st + 1) / s < t[nh][nc] - tg) {
q.push({nh, nc, tmp.st + 1});
cx[nh][nc] = 1;
}
}
}
return 0;
}
void solve ()
{
queue <pii> q;
forinc(i,1,n) forinc(j,1,n) {
t[i][j] = inf;
if(a[i][j] == 'H') {
q.push({i, j});
t[i][j] = 0;
}
else if(a[i][j] == 'M') sta = {i, j};
else if(a[i][j] == 'D') fin = {i, j};
}
// bfs bee
while(q.size()) {
auto x = q.front(); q.pop();
forinc(i,0,3) {
int nh = x.fi + H[i];
int nc = x.se + C[i];
if(valid(nh, nc) && nh != fin.fi && nc != fin.se
&& t[nh][nc] > t[x.fi][x.se] + 1) {
t[nh][nc] = t[x.fi][x.se] + 1;
q.push({nh, nc});
}
}
}
// binary search
int l = 0, r = n * n + 1, ans = -1;
while(l <= r) {
int mid = (l + r) / 2;
if(ok(mid)) {
ans = mid;
l = mid + 1;
}
else r = mid - 1;
}
cout << ans;
}
void read ()
{
cin >> n >> s;
forinc(i,1,n) forinc(j,1,n)
cin >> a[i][j];
solve();
}
main ()
{
#define task "ioi09_mecho"
cin.tie(0) -> sync_with_stdio(0);
if(fopen (task ".inp", "r")) {
freopen (task ".inp", "r", stdin);
freopen (task ".out", "w", stdout);
}
read();
return 0;
}
Compilation message
mecho.cpp:98:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
98 | main ()
| ^~~~
mecho.cpp: In function 'int main()':
mecho.cpp:103:11: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
103 | freopen (task ".inp", "r", stdin);
| ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
mecho.cpp:104:11: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
104 | freopen (task ".out", "w", stdout);
| ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
1 ms |
972 KB |
Output isn't correct |
2 |
Incorrect |
1 ms |
972 KB |
Output isn't correct |
3 |
Incorrect |
1 ms |
972 KB |
Output isn't correct |
4 |
Incorrect |
1 ms |
964 KB |
Output isn't correct |
5 |
Correct |
1 ms |
972 KB |
Output is correct |
6 |
Incorrect |
1 ms |
972 KB |
Output isn't correct |
7 |
Incorrect |
163 ms |
7572 KB |
Output isn't correct |
8 |
Incorrect |
1 ms |
972 KB |
Output isn't correct |
9 |
Incorrect |
1 ms |
972 KB |
Output isn't correct |
10 |
Incorrect |
1 ms |
972 KB |
Output isn't correct |
11 |
Incorrect |
1 ms |
972 KB |
Output isn't correct |
12 |
Incorrect |
1 ms |
1228 KB |
Output isn't correct |
13 |
Incorrect |
1 ms |
1228 KB |
Output isn't correct |
14 |
Incorrect |
1 ms |
1228 KB |
Output isn't correct |
15 |
Incorrect |
1 ms |
972 KB |
Output isn't correct |
16 |
Incorrect |
1 ms |
964 KB |
Output isn't correct |
17 |
Incorrect |
1 ms |
964 KB |
Output isn't correct |
18 |
Incorrect |
1 ms |
972 KB |
Output isn't correct |
19 |
Incorrect |
1 ms |
1100 KB |
Output isn't correct |
20 |
Incorrect |
1 ms |
1100 KB |
Output isn't correct |
21 |
Incorrect |
2 ms |
1100 KB |
Output isn't correct |
22 |
Incorrect |
1 ms |
1092 KB |
Output isn't correct |
23 |
Incorrect |
1 ms |
1228 KB |
Output isn't correct |
24 |
Incorrect |
1 ms |
1228 KB |
Output isn't correct |
25 |
Incorrect |
1 ms |
1228 KB |
Output isn't correct |
26 |
Incorrect |
1 ms |
1228 KB |
Output isn't correct |
27 |
Incorrect |
1 ms |
1228 KB |
Output isn't correct |
28 |
Incorrect |
1 ms |
1228 KB |
Output isn't correct |
29 |
Incorrect |
1 ms |
1228 KB |
Output isn't correct |
30 |
Incorrect |
1 ms |
1360 KB |
Output isn't correct |
31 |
Incorrect |
1 ms |
1356 KB |
Output isn't correct |
32 |
Incorrect |
1 ms |
1356 KB |
Output isn't correct |
33 |
Incorrect |
4 ms |
3540 KB |
Output isn't correct |
34 |
Incorrect |
4 ms |
3508 KB |
Output isn't correct |
35 |
Incorrect |
10 ms |
3540 KB |
Output isn't correct |
36 |
Incorrect |
5 ms |
3908 KB |
Output isn't correct |
37 |
Incorrect |
6 ms |
3896 KB |
Output isn't correct |
38 |
Incorrect |
11 ms |
3916 KB |
Output isn't correct |
39 |
Incorrect |
5 ms |
4288 KB |
Output isn't correct |
40 |
Incorrect |
7 ms |
4292 KB |
Output isn't correct |
41 |
Incorrect |
11 ms |
4300 KB |
Output isn't correct |
42 |
Incorrect |
5 ms |
4684 KB |
Output isn't correct |
43 |
Incorrect |
7 ms |
4684 KB |
Output isn't correct |
44 |
Incorrect |
17 ms |
4752 KB |
Output isn't correct |
45 |
Incorrect |
7 ms |
5188 KB |
Output isn't correct |
46 |
Incorrect |
11 ms |
5064 KB |
Output isn't correct |
47 |
Incorrect |
28 ms |
5132 KB |
Output isn't correct |
48 |
Incorrect |
9 ms |
5464 KB |
Output isn't correct |
49 |
Incorrect |
10 ms |
5572 KB |
Output isn't correct |
50 |
Incorrect |
31 ms |
5492 KB |
Output isn't correct |
51 |
Incorrect |
8 ms |
5836 KB |
Output isn't correct |
52 |
Incorrect |
12 ms |
5964 KB |
Output isn't correct |
53 |
Incorrect |
40 ms |
5972 KB |
Output isn't correct |
54 |
Incorrect |
10 ms |
6340 KB |
Output isn't correct |
55 |
Incorrect |
13 ms |
6340 KB |
Output isn't correct |
56 |
Incorrect |
49 ms |
6368 KB |
Output isn't correct |
57 |
Incorrect |
10 ms |
6708 KB |
Output isn't correct |
58 |
Incorrect |
14 ms |
6732 KB |
Output isn't correct |
59 |
Incorrect |
52 ms |
6804 KB |
Output isn't correct |
60 |
Incorrect |
12 ms |
7108 KB |
Output isn't correct |
61 |
Incorrect |
20 ms |
7164 KB |
Output isn't correct |
62 |
Incorrect |
46 ms |
7188 KB |
Output isn't correct |
63 |
Correct |
122 ms |
7232 KB |
Output is correct |
64 |
Correct |
190 ms |
7236 KB |
Output is correct |
65 |
Correct |
156 ms |
7232 KB |
Output is correct |
66 |
Correct |
112 ms |
7228 KB |
Output is correct |
67 |
Correct |
115 ms |
7224 KB |
Output is correct |
68 |
Correct |
50 ms |
7180 KB |
Output is correct |
69 |
Correct |
51 ms |
7168 KB |
Output is correct |
70 |
Correct |
43 ms |
7288 KB |
Output is correct |
71 |
Correct |
55 ms |
7164 KB |
Output is correct |
72 |
Incorrect |
32 ms |
7244 KB |
Output isn't correct |
73 |
Incorrect |
41 ms |
7756 KB |
Output isn't correct |
74 |
Incorrect |
95 ms |
7704 KB |
Output isn't correct |
75 |
Incorrect |
102 ms |
7776 KB |
Output isn't correct |
76 |
Incorrect |
101 ms |
7700 KB |
Output isn't correct |
77 |
Incorrect |
101 ms |
7688 KB |
Output isn't correct |
78 |
Incorrect |
64 ms |
7620 KB |
Output isn't correct |
79 |
Incorrect |
43 ms |
7684 KB |
Output isn't correct |
80 |
Incorrect |
49 ms |
7696 KB |
Output isn't correct |
81 |
Incorrect |
121 ms |
7664 KB |
Output isn't correct |
82 |
Incorrect |
55 ms |
7652 KB |
Output isn't correct |
83 |
Incorrect |
145 ms |
7656 KB |
Output isn't correct |
84 |
Incorrect |
64 ms |
7520 KB |
Output isn't correct |
85 |
Incorrect |
53 ms |
7568 KB |
Output isn't correct |
86 |
Incorrect |
52 ms |
7636 KB |
Output isn't correct |
87 |
Incorrect |
65 ms |
7532 KB |
Output isn't correct |
88 |
Incorrect |
50 ms |
7424 KB |
Output isn't correct |
89 |
Incorrect |
72 ms |
7448 KB |
Output isn't correct |
90 |
Incorrect |
100 ms |
7424 KB |
Output isn't correct |
91 |
Incorrect |
50 ms |
7544 KB |
Output isn't correct |
92 |
Incorrect |
55 ms |
7620 KB |
Output isn't correct |