// credit: bieoiibe
#include <bits/stdc++.h>
#define pb push_back
#define ppb pop_back
#define fr first
#define sc second
#define all(v) v.begin(), v.end()
#define mod (long long)(1e9 + 7)
#define eps (long long)(1e-9)
#define vektor vector
using namespace std;
using ll = long long;
using ull = unsigned long long;
using ld = long double;
const ll Mod = 1e9 + 7;
void solve(){
int n, m, ans = 0;
cin >> n >> m;
vector <vector <char>> a(n + 1, vector <char> (m + 1));
vector <vector <int>> v(n + 1, vector <int> (m + 1, 0)), val(n + 1, vector <int> (m + 1, 0));
int col[4] = {0, 1, 0, -1},
row[4] = {1, 0, -1, 0};
for(int i = 1; i <= n; i ++) {
for(int j = 1; j <= m; j ++) cin >> a[i][j];
}
queue <pair <int, int>> q, w;
q.push({1, 1});
v[1][1] = val[1][1] = 1;
while(!q.empty()){
int x1 = q.front().fr, y1 = q.front().sc;
q.pop();
for(int i = 0; i < 4; i ++){
int x = x1 + col[i], y = y1 + row[i];
if(x > n || x < 1 || y > m || y < 1 || a[x][y] == '.' || v[x][y]) continue;
val[x][y] = val[x1][y1];
if(a[x][y] != a[x1][y1]) val[x][y] ++, w.push({x, y});
else v[x][y] = 1, q.push({x, y});
}
if(q.empty()){
// cout << w.size() << "\n";
while(!q.empty() && v[w.front().fr][w.front().sc]) w.pop();
if(w.empty()) break;
v[w.front().fr][w.front().sc] = 1;
q.push(w.front());
w.pop();
}
}
for(int i = 1; i <= n; i ++)
for(int j = 1; j <= m; j ++) ans = max(ans, val[i][j]);
cout << ans;
}
signed main()
{
cin.tie(0)->sync_with_stdio(0);
if(fopen("blank.inp", "r")){
freopen("blank.inp", "r", stdin);
freopen("blank.out", "w", stdout);
}
// cout << 1; return 0;
ll n = 1;
// cin >> n;
while(n) {
solve();
n --;
cout << "\n";
}
cerr << "Time elapsed: " << 1.0 * clock() / CLOCKS_PER_SEC << " s.\n";
}
Compilation message
tracks.cpp: In function 'int main()':
tracks.cpp:76:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
76 | freopen("blank.inp", "r", stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
tracks.cpp:77:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
77 | freopen("blank.out", "w", stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
19 ms |
2896 KB |
Output is correct |
2 |
Correct |
1 ms |
336 KB |
Output is correct |
3 |
Correct |
1 ms |
460 KB |
Output is correct |
4 |
Correct |
10 ms |
2244 KB |
Output is correct |
5 |
Correct |
4 ms |
1104 KB |
Output is correct |
6 |
Correct |
1 ms |
336 KB |
Output is correct |
7 |
Correct |
1 ms |
336 KB |
Output is correct |
8 |
Correct |
1 ms |
336 KB |
Output is correct |
9 |
Correct |
1 ms |
336 KB |
Output is correct |
10 |
Correct |
4 ms |
1104 KB |
Output is correct |
11 |
Correct |
3 ms |
848 KB |
Output is correct |
12 |
Correct |
8 ms |
1400 KB |
Output is correct |
13 |
Correct |
4 ms |
1104 KB |
Output is correct |
14 |
Correct |
4 ms |
1104 KB |
Output is correct |
15 |
Correct |
21 ms |
2896 KB |
Output is correct |
16 |
Correct |
20 ms |
3152 KB |
Output is correct |
17 |
Correct |
13 ms |
2896 KB |
Output is correct |
18 |
Correct |
8 ms |
2264 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
1360 KB |
Output is correct |
2 |
Correct |
65 ms |
15956 KB |
Output is correct |
3 |
Correct |
433 ms |
157372 KB |
Output is correct |
4 |
Correct |
134 ms |
37192 KB |
Output is correct |
5 |
Correct |
255 ms |
88920 KB |
Output is correct |
6 |
Correct |
998 ms |
176716 KB |
Output is correct |
7 |
Correct |
3 ms |
1360 KB |
Output is correct |
8 |
Correct |
3 ms |
1360 KB |
Output is correct |
9 |
Correct |
3 ms |
1104 KB |
Output is correct |
10 |
Correct |
2 ms |
592 KB |
Output is correct |
11 |
Correct |
3 ms |
1360 KB |
Output is correct |
12 |
Correct |
1 ms |
592 KB |
Output is correct |
13 |
Correct |
67 ms |
15952 KB |
Output is correct |
14 |
Correct |
51 ms |
9296 KB |
Output is correct |
15 |
Correct |
26 ms |
10260 KB |
Output is correct |
16 |
Correct |
33 ms |
6820 KB |
Output is correct |
17 |
Correct |
180 ms |
40408 KB |
Output is correct |
18 |
Correct |
110 ms |
39636 KB |
Output is correct |
19 |
Correct |
107 ms |
36644 KB |
Output is correct |
20 |
Correct |
102 ms |
34248 KB |
Output is correct |
21 |
Correct |
254 ms |
91816 KB |
Output is correct |
22 |
Correct |
231 ms |
88904 KB |
Output is correct |
23 |
Correct |
349 ms |
76616 KB |
Output is correct |
24 |
Correct |
207 ms |
89672 KB |
Output is correct |
25 |
Correct |
445 ms |
157512 KB |
Output is correct |
26 |
Correct |
510 ms |
120540 KB |
Output is correct |
27 |
Correct |
702 ms |
159420 KB |
Output is correct |
28 |
Correct |
1000 ms |
176784 KB |
Output is correct |
29 |
Correct |
940 ms |
176484 KB |
Output is correct |
30 |
Correct |
835 ms |
170236 KB |
Output is correct |
31 |
Correct |
910 ms |
102240 KB |
Output is correct |
32 |
Correct |
620 ms |
159392 KB |
Output is correct |