#include <bits/stdc++.h>
#define all(x) begin(x),end(x)
#define fir first
#define sec second
#define sz(x) x.size()
#define pb push_back
using namespace std;
using ll = long long;
using vi = vector<int>;
using pi = pair<int,int>;
using pdb = pair<double,double>;
using pll = pair<ll,ll>;
using vll = vector<ll>;
const double EPS = (1e-6);
void setio(string s){
freopen((s + ".in").c_str(),"r",stdin);
freopen((s + ".out").c_str(),"w",stdout);
}
vi dr = {1, -1, 0, 0};
vi dc = {0, 0, 1, -1};
bool valid(int ans, int n, int s,pi m, vector<pi>& hives, vector<string>& grid){
bool ok = 1;
//1 = mecho, -1 = bee
vector<vi> occupy(n, vi(n));
vector<vi> dist(n, vi (n, -1));
queue<pi> mecho;
mecho.push(m);
dist[m.fir][m.sec] = 0;
occupy[m.fir][m.sec] = 1;
queue<pi> bees;
for(auto& i :hives){
bees.push(i);
dist[i.fir][i.sec] = 0;
occupy[i.fir][i.sec] = -1;
}
while (!bees.empty()){
pi cur = bees.front();
if (dist[cur.fir][cur.sec] == ans){
break;
}
bees.pop();
for(int i{}; i < 4; i++){
if (cur.fir+dr[i] < 0 || cur.fir+dr[i] >= n || cur.sec+dc[i] < 0 || cur.sec+dc[i] >= n) continue;
if (occupy[cur.fir+dr[i]][cur.sec+dc[i]] >= 0 && grid[cur.fir+dr[i]][cur.sec+dc[i]] != 'T' && grid[cur.fir+dr[i]][cur.sec+dc[i]] != 'D'){
if (cur.fir+dr[i] == m.fir && cur.sec+dc[i] == m.sec) ok = 0;
occupy[cur.fir+dr[i]][cur.sec+dc[i]] = -1;
dist[cur.fir+dr[i]][cur.sec+dc[i]] = dist[cur.fir][cur.sec]+1;
bees.push({cur.fir+dr[i], cur.sec+dc[i]});
}
}
}
int cur_time = ans+1;
bool found = 0;
while (!found && ok && !mecho.empty() && !bees.empty()){
while (!mecho.empty()){
pi cur = mecho.front();
if (occupy[cur.fir][cur.sec] == -1){
mecho.pop();
continue;
}
if (dist[cur.fir][cur.sec] == (cur_time-ans)*s) break;
mecho.pop();
for(int i{}; i < 4; i++){
if (cur.fir+dr[i] < 0 || cur.fir+dr[i] >= n || cur.sec+dc[i] < 0 || cur.sec+dc[i] >= n) continue;
if (occupy[cur.fir+dr[i]][cur.sec+dc[i]] == 0 && grid[cur.fir+dr[i]][cur.sec+dc[i]] != 'T'){
occupy[cur.fir+dr[i]][cur.sec+dc[i]] = 1;
dist[cur.fir+dr[i]][cur.sec+dc[i]] = dist[cur.fir][cur.sec]+1;
mecho.push({cur.fir+dr[i], cur.sec+dc[i]});
}
if (grid[cur.fir+dr[i]][cur.sec+dc[i]] == 'D'){
found = 1;
break;
}
}
}
while (!bees.empty()){
pi cur = bees.front();
if (dist[cur.fir][cur.sec] == cur_time){
break;
}
bees.pop();
for(int i{}; i < 4; i++){
if (cur.fir+dr[i] < 0 || cur.fir+dr[i] >= n || cur.sec+dc[i] < 0 || cur.sec+dc[i] >= n) continue;
if (occupy[cur.fir+dr[i]][cur.sec+dc[i]] >= 0 && grid[cur.fir+dr[i]][cur.sec+dc[i]] != 'T' && grid[cur.fir+dr[i]][cur.sec+dc[i]] != 'D'){
occupy[cur.fir+dr[i]][cur.sec+dc[i]] = -1;
dist[cur.fir+dr[i]][cur.sec+dc[i]] = dist[cur.fir][cur.sec]+1;
bees.push({cur.fir+dr[i], cur.sec+dc[i]});
}
}
}
cur_time++;
/*
for(int i{}; i < n; i++){
for(int j{};j < n; j++){
cout << dist[i][j] << '\t';
}
cout << '\n';
}
cout << '\n';
for(int i{}; i < n; i++){
for(int j{};j < n; j++){
cout << occupy[i][j] << '\t';
}
cout << '\n';
}
cout << '\n';
*/
}
return (found && ok);
}
void solve(){
int n, s;
cin >> n >> s;
vector<string> grid(n);
for(auto& i : grid) cin >> i;
vector<pi> hives;
pi m;
for(int i{}; i < n; i++){
for(int j{};j < n; j++){
if (grid[i][j] == 'M') m = {i,j};
else if (grid[i][j] == 'H'){
hives.pb({i,j});
}
}
}
int lo = 0, hi = n*n;
while (hi > lo){
int mid = lo + (hi-lo+1)/2;
if (valid(mid, n, s, m, hives, grid)){
lo = mid;
}else hi = mid-1;
}
cout << (valid(lo,n,s,m,hives,grid) ? lo : -1);
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
int t = 1;
while(t--){
solve();
}
return 0;
}
Compilation message
mecho.cpp: In function 'void setio(std::string)':
mecho.cpp:18:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
18 | freopen((s + ".in").c_str(),"r",stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mecho.cpp:19:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
19 | freopen((s + ".out").c_str(),"w",stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
212 KB |
Output is correct |
2 |
Correct |
0 ms |
212 KB |
Output is correct |
3 |
Correct |
0 ms |
212 KB |
Output is correct |
4 |
Correct |
0 ms |
212 KB |
Output is correct |
5 |
Correct |
1 ms |
212 KB |
Output is correct |
6 |
Correct |
0 ms |
212 KB |
Output is correct |
7 |
Correct |
410 ms |
6220 KB |
Output is correct |
8 |
Correct |
0 ms |
212 KB |
Output is correct |
9 |
Correct |
0 ms |
212 KB |
Output is correct |
10 |
Correct |
1 ms |
212 KB |
Output is correct |
11 |
Correct |
1 ms |
212 KB |
Output is correct |
12 |
Correct |
1 ms |
340 KB |
Output is correct |
13 |
Correct |
1 ms |
340 KB |
Output is correct |
14 |
Correct |
2 ms |
340 KB |
Output is correct |
15 |
Correct |
1 ms |
212 KB |
Output is correct |
16 |
Correct |
1 ms |
212 KB |
Output is correct |
17 |
Correct |
0 ms |
212 KB |
Output is correct |
18 |
Correct |
1 ms |
212 KB |
Output is correct |
19 |
Correct |
0 ms |
212 KB |
Output is correct |
20 |
Correct |
1 ms |
212 KB |
Output is correct |
21 |
Correct |
1 ms |
340 KB |
Output is correct |
22 |
Correct |
1 ms |
212 KB |
Output is correct |
23 |
Correct |
1 ms |
340 KB |
Output is correct |
24 |
Correct |
1 ms |
340 KB |
Output is correct |
25 |
Correct |
1 ms |
340 KB |
Output is correct |
26 |
Correct |
2 ms |
328 KB |
Output is correct |
27 |
Correct |
1 ms |
340 KB |
Output is correct |
28 |
Correct |
2 ms |
340 KB |
Output is correct |
29 |
Correct |
1 ms |
340 KB |
Output is correct |
30 |
Correct |
1 ms |
340 KB |
Output is correct |
31 |
Correct |
2 ms |
340 KB |
Output is correct |
32 |
Correct |
2 ms |
340 KB |
Output is correct |
33 |
Correct |
32 ms |
1436 KB |
Output is correct |
34 |
Correct |
30 ms |
1416 KB |
Output is correct |
35 |
Correct |
48 ms |
1428 KB |
Output is correct |
36 |
Correct |
43 ms |
1748 KB |
Output is correct |
37 |
Correct |
42 ms |
1748 KB |
Output is correct |
38 |
Correct |
64 ms |
1748 KB |
Output is correct |
39 |
Correct |
65 ms |
2164 KB |
Output is correct |
40 |
Correct |
57 ms |
2160 KB |
Output is correct |
41 |
Correct |
99 ms |
2132 KB |
Output is correct |
42 |
Correct |
80 ms |
2612 KB |
Output is correct |
43 |
Correct |
70 ms |
2600 KB |
Output is correct |
44 |
Correct |
109 ms |
2596 KB |
Output is correct |
45 |
Correct |
100 ms |
3056 KB |
Output is correct |
46 |
Correct |
96 ms |
3052 KB |
Output is correct |
47 |
Correct |
124 ms |
3040 KB |
Output is correct |
48 |
Correct |
119 ms |
3596 KB |
Output is correct |
49 |
Correct |
107 ms |
3664 KB |
Output is correct |
50 |
Correct |
175 ms |
3540 KB |
Output is correct |
51 |
Correct |
136 ms |
4144 KB |
Output is correct |
52 |
Correct |
125 ms |
4264 KB |
Output is correct |
53 |
Correct |
190 ms |
4136 KB |
Output is correct |
54 |
Correct |
200 ms |
4732 KB |
Output is correct |
55 |
Correct |
144 ms |
4792 KB |
Output is correct |
56 |
Correct |
293 ms |
4800 KB |
Output is correct |
57 |
Correct |
192 ms |
5420 KB |
Output is correct |
58 |
Correct |
165 ms |
5392 KB |
Output is correct |
59 |
Correct |
342 ms |
5544 KB |
Output is correct |
60 |
Correct |
212 ms |
6084 KB |
Output is correct |
61 |
Correct |
209 ms |
6080 KB |
Output is correct |
62 |
Correct |
394 ms |
6124 KB |
Output is correct |
63 |
Correct |
427 ms |
6072 KB |
Output is correct |
64 |
Correct |
438 ms |
6232 KB |
Output is correct |
65 |
Correct |
409 ms |
6296 KB |
Output is correct |
66 |
Correct |
441 ms |
6088 KB |
Output is correct |
67 |
Correct |
424 ms |
6168 KB |
Output is correct |
68 |
Correct |
426 ms |
6108 KB |
Output is correct |
69 |
Correct |
353 ms |
6116 KB |
Output is correct |
70 |
Correct |
437 ms |
6100 KB |
Output is correct |
71 |
Correct |
434 ms |
6104 KB |
Output is correct |
72 |
Correct |
475 ms |
6100 KB |
Output is correct |
73 |
Correct |
411 ms |
6512 KB |
Output is correct |
74 |
Correct |
471 ms |
6516 KB |
Output is correct |
75 |
Correct |
473 ms |
6408 KB |
Output is correct |
76 |
Correct |
568 ms |
6388 KB |
Output is correct |
77 |
Correct |
470 ms |
6372 KB |
Output is correct |
78 |
Correct |
492 ms |
6440 KB |
Output is correct |
79 |
Correct |
466 ms |
6336 KB |
Output is correct |
80 |
Correct |
432 ms |
6336 KB |
Output is correct |
81 |
Correct |
433 ms |
6412 KB |
Output is correct |
82 |
Correct |
454 ms |
6516 KB |
Output is correct |
83 |
Correct |
430 ms |
6440 KB |
Output is correct |
84 |
Correct |
439 ms |
6364 KB |
Output is correct |
85 |
Correct |
479 ms |
6308 KB |
Output is correct |
86 |
Correct |
447 ms |
6472 KB |
Output is correct |
87 |
Correct |
445 ms |
6316 KB |
Output is correct |
88 |
Correct |
435 ms |
6272 KB |
Output is correct |
89 |
Correct |
491 ms |
6300 KB |
Output is correct |
90 |
Correct |
469 ms |
6348 KB |
Output is correct |
91 |
Correct |
401 ms |
6240 KB |
Output is correct |
92 |
Correct |
440 ms |
6288 KB |
Output is correct |