#include <bits/stdc++.h>
using namespace std;
#define task ""
#define fi first
#define se second
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define FOR(i, a, b) for (int i = (a), _b = (b); i <= _b; ++i)
#define FORD(i, a, b) for (int i = (b), _a = (a); i >= _a; --i)
template <typename T1, typename T2> bool minimize(T1 &a, T2 b) {
if (a > b) {a = b; return true;} return false;
}
template <typename T1, typename T2> bool maximize(T1 &a, T2 b) {
if (a < b) {a = b; return true;} return false;
}
const int dx[] = {-1, 0, 0, +1};
const int dy[] = {0, -1, +1, 0};
const int MAX = 4000;
int n, m;
int ans = 0;
int d[MAX][MAX];
char a[MAX][MAX];
int main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
if (fopen(task".inp", "r")) {
freopen(task".inp", "r", stdin);
freopen(task".out", "w", stdout);
}
cin >> n >> m;
for (int i = 0; i < n; ++i)
for (int j = 0; j < m; ++j)
cin >> a[i][j];
memset(d, 0x3f, sizeof d);
deque<pair<int, int>> dq;
dq.push_front({0, 0});
d[0][0] = 1;
while (dq.size()) {
int u = dq.front().fi;
int v = dq.front().se;
maximize(ans, d[u][v]);
dq.pop_front();
for (int i = 0; i < 4; ++i) {
int x = u + dx[i], y = v + dy[i];
if (x < 0 || x >= n) continue;
if (y < 0 || y >= m) continue;
if (a[x][y] != '.') {
int w = a[u][v] != a[x][y];
if (minimize(d[x][y], d[u][v] + w)) {
if (w) dq.push_back({x, y});
else dq.push_front({x, y});
}
}
}
}
cout << ans;
return 0;
}
Compilation message
tracks.cpp: In function 'int main()':
tracks.cpp:32:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
32 | freopen(task".inp", "r", stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
tracks.cpp:33:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
33 | freopen(task".out", "w", stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
54 ms |
65140 KB |
Output is correct |
2 |
Correct |
27 ms |
62924 KB |
Output is correct |
3 |
Correct |
35 ms |
63092 KB |
Output is correct |
4 |
Correct |
35 ms |
65208 KB |
Output is correct |
5 |
Correct |
28 ms |
64076 KB |
Output is correct |
6 |
Correct |
26 ms |
62988 KB |
Output is correct |
7 |
Correct |
26 ms |
63044 KB |
Output is correct |
8 |
Correct |
28 ms |
63188 KB |
Output is correct |
9 |
Correct |
26 ms |
63308 KB |
Output is correct |
10 |
Correct |
30 ms |
63928 KB |
Output is correct |
11 |
Correct |
32 ms |
63820 KB |
Output is correct |
12 |
Correct |
34 ms |
64100 KB |
Output is correct |
13 |
Correct |
33 ms |
64084 KB |
Output is correct |
14 |
Correct |
31 ms |
64076 KB |
Output is correct |
15 |
Correct |
40 ms |
65092 KB |
Output is correct |
16 |
Correct |
42 ms |
65108 KB |
Output is correct |
17 |
Correct |
40 ms |
65012 KB |
Output is correct |
18 |
Correct |
36 ms |
65168 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
36 ms |
77896 KB |
Output is correct |
2 |
Correct |
79 ms |
69260 KB |
Output is correct |
3 |
Correct |
357 ms |
94272 KB |
Output is correct |
4 |
Correct |
113 ms |
73980 KB |
Output is correct |
5 |
Correct |
222 ms |
83368 KB |
Output is correct |
6 |
Correct |
773 ms |
109344 KB |
Output is correct |
7 |
Correct |
31 ms |
78568 KB |
Output is correct |
8 |
Correct |
31 ms |
77908 KB |
Output is correct |
9 |
Correct |
28 ms |
62976 KB |
Output is correct |
10 |
Correct |
26 ms |
62912 KB |
Output is correct |
11 |
Correct |
32 ms |
78292 KB |
Output is correct |
12 |
Correct |
28 ms |
63440 KB |
Output is correct |
13 |
Correct |
76 ms |
69332 KB |
Output is correct |
14 |
Correct |
54 ms |
67280 KB |
Output is correct |
15 |
Correct |
52 ms |
67820 KB |
Output is correct |
16 |
Correct |
47 ms |
65100 KB |
Output is correct |
17 |
Correct |
152 ms |
74808 KB |
Output is correct |
18 |
Correct |
125 ms |
74576 KB |
Output is correct |
19 |
Correct |
110 ms |
73852 KB |
Output is correct |
20 |
Correct |
101 ms |
73052 KB |
Output is correct |
21 |
Correct |
218 ms |
84168 KB |
Output is correct |
22 |
Correct |
241 ms |
83532 KB |
Output is correct |
23 |
Correct |
264 ms |
80324 KB |
Output is correct |
24 |
Correct |
220 ms |
84108 KB |
Output is correct |
25 |
Correct |
467 ms |
94220 KB |
Output is correct |
26 |
Correct |
522 ms |
138752 KB |
Output is correct |
27 |
Correct |
686 ms |
134884 KB |
Output is correct |
28 |
Correct |
764 ms |
109420 KB |
Output is correct |
29 |
Correct |
763 ms |
106660 KB |
Output is correct |
30 |
Correct |
718 ms |
111032 KB |
Output is correct |
31 |
Correct |
530 ms |
86028 KB |
Output is correct |
32 |
Correct |
625 ms |
117256 KB |
Output is correct |