#include<bits/stdc++.h>
#define mp make_pair
#define pb push_back
using namespace std;
using pii = pair < short, short >;
const int N = 805;
const int dx[] = {1, -1, 0, 0}, dy[] = {0, 0, 1, -1};
char a[N][N];
pii mecho, home;
int n, s, hive[N][N];
bool used[N][N];
void hive_bfs(){
memset( hive, 11, sizeof(hive) );
queue < pii > q;
for(int i = 0 ; i < n ; i++) for(int j = 0 ; j < n ; j++){
if( a[i][j] == 'H' ){
q.push( mp( i, j ) );
hive[i][j] = 0;
}
}
int dis = 0;
while( !q.empty() ){
dis += s;
int sz = q.size();
while( sz-- ){
short int x, y;
tie(x, y) = q.front();
q.pop();
for(int i = 0 ; i < 4 ; i++){
short int tx = x+dx[i], ty = y+dy[i];
if( tx < 0 || ty < 0 || tx >= n || ty >= n ) continue;
if( a[tx][ty] == 'G' && hive[tx][ty] > 2e6 ){
hive[tx][ty] = dis;
q.push( mp( tx, ty ) );
}
}
}
}
/*
for(int i = 0 ; i < n ; i++){
for(int j = 0 ; j < n ; j++){
if( hive[i][j] > 2e6 ) printf("@@ ");
else printf("%2d ", hive[i][j]);
}
printf("\n");
}
*/
}
bool mecho_bfs(int start_time){
memset( used, 0, sizeof(used) );
if( start_time > hive[home.first][home.second] ){
return false;
}
queue < pii > q;
q.push( mecho );
int dis = start_time;
while( !q.empty() ){
dis++;
// cout << "dis " << dis << " : ";
int sz = q.size();
while( sz-- ){
short int x, y;
tie(x, y) = q.front();
q.pop();
for(int i = 0 ; i < 4 ; i++){
short int tx = x+dx[i], ty = y+dy[i];
if( tx < 0 || ty < 0 || tx >= n || ty >= n ) continue;
if( !used[tx][ty] && a[tx][ty] == 'G' && hive[tx][ty] > dis ){
used[tx][ty] = 1;
if( used[ home.first ][ home.second ] ){
return true;
}
// cout << "( " << tx << ',' << ty << " ), ";
q.push( mp( tx, ty ) );
}
}
}
// cout << endl;
}
return used[ home.first ][ home.second ];
}
int main(){
scanf("%d %d", &n, &s);
for(int i = 0 ; i < n ; i++){
scanf("%s", a[i]);
}
for(int i = 0 ; i < n ; i++) for(int j = 0 ; j < n ; j++){
if( a[i][j] == 'D' ){
home = mp( i, j );
a[i][j] = 'G';
}
if( a[i][j] == 'M' ){
mecho = mp( i, j );
}
}
hive_bfs();
if( !mecho_bfs( 0 ) ){
printf("-1\n");
return 0;
}
int l = 0, r = n*n, res;
while( l <= r ){
int mid = (l+r)/2;
if( mecho_bfs( s*(mid) ) ){
res = mid;
l = mid+1;
} else {
r = mid-1;
}
}
/*
int res = 0;
while( mecho_bfs( s*(res+1) ) ) res++;
*/
cout << res << endl;
}
Compilation message
mecho.cpp: In function 'int main()':
mecho.cpp:95:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d %d", &n, &s);
~~~~~^~~~~~~~~~~~~~~~~
mecho.cpp:97:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%s", a[i]);
~~~~~^~~~~~~~~~~~
mecho.cpp:132:10: warning: 'res' may be used uninitialized in this function [-Wmaybe-uninitialized]
cout << res << endl;
^~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
5 ms |
3456 KB |
Output is correct |
2 |
Incorrect |
5 ms |
3456 KB |
Output isn't correct |
3 |
Correct |
6 ms |
3456 KB |
Output is correct |
4 |
Incorrect |
6 ms |
3456 KB |
Output isn't correct |
5 |
Correct |
5 ms |
3456 KB |
Output is correct |
6 |
Incorrect |
6 ms |
3456 KB |
Output isn't correct |
7 |
Incorrect |
76 ms |
4096 KB |
Output isn't correct |
8 |
Correct |
6 ms |
3456 KB |
Output is correct |
9 |
Correct |
5 ms |
3456 KB |
Output is correct |
10 |
Correct |
5 ms |
3456 KB |
Output is correct |
11 |
Correct |
5 ms |
3456 KB |
Output is correct |
12 |
Incorrect |
5 ms |
3584 KB |
Output isn't correct |
13 |
Incorrect |
6 ms |
3584 KB |
Output isn't correct |
14 |
Correct |
5 ms |
3584 KB |
Output is correct |
15 |
Correct |
5 ms |
3456 KB |
Output is correct |
16 |
Correct |
5 ms |
3584 KB |
Output is correct |
17 |
Correct |
6 ms |
3584 KB |
Output is correct |
18 |
Correct |
5 ms |
3456 KB |
Output is correct |
19 |
Correct |
6 ms |
3584 KB |
Output is correct |
20 |
Correct |
5 ms |
3456 KB |
Output is correct |
21 |
Correct |
5 ms |
3456 KB |
Output is correct |
22 |
Correct |
5 ms |
3584 KB |
Output is correct |
23 |
Correct |
5 ms |
3456 KB |
Output is correct |
24 |
Correct |
6 ms |
3584 KB |
Output is correct |
25 |
Correct |
5 ms |
3584 KB |
Output is correct |
26 |
Correct |
5 ms |
3584 KB |
Output is correct |
27 |
Correct |
6 ms |
3556 KB |
Output is correct |
28 |
Correct |
5 ms |
3584 KB |
Output is correct |
29 |
Correct |
6 ms |
3584 KB |
Output is correct |
30 |
Correct |
6 ms |
3584 KB |
Output is correct |
31 |
Correct |
5 ms |
3584 KB |
Output is correct |
32 |
Correct |
6 ms |
3584 KB |
Output is correct |
33 |
Correct |
9 ms |
3712 KB |
Output is correct |
34 |
Runtime error |
505 ms |
66560 KB |
Execution killed with signal 9 (could be triggered by violating memory limits) |
35 |
Correct |
18 ms |
3840 KB |
Output is correct |
36 |
Correct |
8 ms |
3840 KB |
Output is correct |
37 |
Runtime error |
499 ms |
66560 KB |
Execution killed with signal 9 (could be triggered by violating memory limits) |
38 |
Correct |
21 ms |
3840 KB |
Output is correct |
39 |
Correct |
11 ms |
3840 KB |
Output is correct |
40 |
Runtime error |
490 ms |
66560 KB |
Execution killed with signal 9 (could be triggered by violating memory limits) |
41 |
Correct |
22 ms |
3812 KB |
Output is correct |
42 |
Correct |
9 ms |
3968 KB |
Output is correct |
43 |
Runtime error |
519 ms |
66560 KB |
Execution killed with signal 9 (could be triggered by violating memory limits) |
44 |
Correct |
34 ms |
3968 KB |
Output is correct |
45 |
Correct |
12 ms |
3968 KB |
Output is correct |
46 |
Runtime error |
551 ms |
66560 KB |
Execution killed with signal 9 (could be triggered by violating memory limits) |
47 |
Correct |
38 ms |
3968 KB |
Output is correct |
48 |
Correct |
14 ms |
3968 KB |
Output is correct |
49 |
Runtime error |
468 ms |
66560 KB |
Execution killed with signal 9 (could be triggered by violating memory limits) |
50 |
Correct |
51 ms |
4088 KB |
Output is correct |
51 |
Correct |
14 ms |
3968 KB |
Output is correct |
52 |
Runtime error |
493 ms |
66560 KB |
Execution killed with signal 9 (could be triggered by violating memory limits) |
53 |
Correct |
54 ms |
3964 KB |
Output is correct |
54 |
Correct |
16 ms |
3968 KB |
Output is correct |
55 |
Runtime error |
453 ms |
66560 KB |
Execution killed with signal 9 (could be triggered by violating memory limits) |
56 |
Correct |
68 ms |
4096 KB |
Output is correct |
57 |
Correct |
14 ms |
4096 KB |
Output is correct |
58 |
Runtime error |
473 ms |
66560 KB |
Execution killed with signal 9 (could be triggered by violating memory limits) |
59 |
Correct |
75 ms |
4216 KB |
Output is correct |
60 |
Correct |
18 ms |
4096 KB |
Output is correct |
61 |
Runtime error |
477 ms |
66560 KB |
Execution killed with signal 9 (could be triggered by violating memory limits) |
62 |
Correct |
85 ms |
4088 KB |
Output is correct |
63 |
Correct |
150 ms |
4096 KB |
Output is correct |
64 |
Runtime error |
439 ms |
66560 KB |
Execution killed with signal 9 (could be triggered by violating memory limits) |
65 |
Correct |
171 ms |
4216 KB |
Output is correct |
66 |
Correct |
166 ms |
4060 KB |
Output is correct |
67 |
Correct |
34 ms |
4096 KB |
Output is correct |
68 |
Correct |
53 ms |
4096 KB |
Output is correct |
69 |
Correct |
61 ms |
4088 KB |
Output is correct |
70 |
Correct |
39 ms |
4096 KB |
Output is correct |
71 |
Correct |
47 ms |
4088 KB |
Output is correct |
72 |
Incorrect |
37 ms |
4088 KB |
Output isn't correct |
73 |
Incorrect |
95 ms |
4204 KB |
Output isn't correct |
74 |
Correct |
72 ms |
4324 KB |
Output is correct |
75 |
Correct |
78 ms |
4204 KB |
Output is correct |
76 |
Correct |
67 ms |
4212 KB |
Output is correct |
77 |
Correct |
62 ms |
4212 KB |
Output is correct |
78 |
Correct |
31 ms |
4344 KB |
Output is correct |
79 |
Correct |
63 ms |
4316 KB |
Output is correct |
80 |
Correct |
67 ms |
4216 KB |
Output is correct |
81 |
Correct |
76 ms |
4216 KB |
Output is correct |
82 |
Correct |
64 ms |
4224 KB |
Output is correct |
83 |
Correct |
72 ms |
4304 KB |
Output is correct |
84 |
Correct |
76 ms |
4316 KB |
Output is correct |
85 |
Correct |
87 ms |
4224 KB |
Output is correct |
86 |
Correct |
82 ms |
4300 KB |
Output is correct |
87 |
Correct |
88 ms |
4224 KB |
Output is correct |
88 |
Correct |
78 ms |
4224 KB |
Output is correct |
89 |
Correct |
70 ms |
4176 KB |
Output is correct |
90 |
Correct |
91 ms |
4216 KB |
Output is correct |
91 |
Correct |
97 ms |
4344 KB |
Output is correct |
92 |
Correct |
99 ms |
4216 KB |
Output is correct |