#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;
typedef pair<int, int> pi;
typedef pair<ll,ll> pl;
typedef pair<ld,ld> pd;
typedef vector<int> vi;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<cd> vcd;
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;
#define FOR(i, a, b) for (int i=a; i<(b); i++)
#define F0R(i, a) for (int i=0; i<(a); i++)
#define FORd(i,a,b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i,a) for (int i = (a)-1; i >= 0; i--)
#define sz(x) (int)(x).size()
#define mp make_pair
#define pb push_back
#define f first
#define s second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()
const int MOD = 1000000007;
const ll INF = 1e18;
const int MX = 4000*4000;
int H,W, dist[4000][4000];
string g[4000];
int xd[4] = {0,1,0,-1}, yd[4] = {1,0,-1,0};
int main() {
ios_base::sync_with_stdio(0); cin.tie(0);
cin >> H >> W;
F0R(i,H) cin >> g[i];
F0R(i,H) F0R(j,W) dist[i][j] = MOD;
deque<int> q; dist[0][0] = 0; q.pb(0);
int ans = 0;
while (sz(q)) {
int x = q.front(); q.pop_front();
int y = x%W; x /= W;
ans = max(ans,dist[x][y]);
F0R(i,4) {
int X = x+xd[i], Y = y+yd[i];
if (X < 0 || X >= H || Y < 0 || Y >= W) continue;
if (g[X][Y] == '.') continue;
if (g[X][Y] == g[x][y]) {
if (dist[X][Y] > dist[x][y]) {
dist[X][Y] = dist[x][y];
q.pb(W*X+Y);
}
} else {
if (dist[X][Y] > dist[x][y]+1) {
dist[X][Y] = dist[x][y]+1;
q.pb(W*X+Y);
}
}
}
}
cout << ans+1;
}
/* Look for:
* the exact constraints (multiple sets are too slow for n=10^6 :( )
* special cases (n=1?)
* overflow (ll vs int?)
* array bounds
*/
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
373 ms |
4028 KB |
Output isn't correct |
| 2 |
Correct |
3 ms |
4028 KB |
Output is correct |
| 3 |
Incorrect |
3 ms |
4028 KB |
Output isn't correct |
| 4 |
Incorrect |
40 ms |
4028 KB |
Output isn't correct |
| 5 |
Incorrect |
21 ms |
4028 KB |
Output isn't correct |
| 6 |
Correct |
3 ms |
4028 KB |
Output is correct |
| 7 |
Incorrect |
4 ms |
4028 KB |
Output isn't correct |
| 8 |
Incorrect |
4 ms |
4028 KB |
Output isn't correct |
| 9 |
Incorrect |
4 ms |
4028 KB |
Output isn't correct |
| 10 |
Incorrect |
13 ms |
4028 KB |
Output isn't correct |
| 11 |
Incorrect |
8 ms |
4028 KB |
Output isn't correct |
| 12 |
Incorrect |
92 ms |
4028 KB |
Output isn't correct |
| 13 |
Incorrect |
23 ms |
4028 KB |
Output isn't correct |
| 14 |
Incorrect |
21 ms |
4028 KB |
Output isn't correct |
| 15 |
Incorrect |
187 ms |
5088 KB |
Output isn't correct |
| 16 |
Incorrect |
386 ms |
5464 KB |
Output isn't correct |
| 17 |
Incorrect |
179 ms |
5464 KB |
Output isn't correct |
| 18 |
Incorrect |
36 ms |
5464 KB |
Output isn't correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
14 ms |
17864 KB |
Output is correct |
| 2 |
Incorrect |
989 ms |
17864 KB |
Output isn't correct |
| 3 |
Execution timed out |
2059 ms |
100088 KB |
Time limit exceeded |
| 4 |
Execution timed out |
2067 ms |
100088 KB |
Time limit exceeded |
| 5 |
Correct |
184 ms |
100088 KB |
Output is correct |
| 6 |
Execution timed out |
2061 ms |
100748 KB |
Time limit exceeded |
| 7 |
Correct |
14 ms |
100748 KB |
Output is correct |
| 8 |
Correct |
13 ms |
100748 KB |
Output is correct |
| 9 |
Incorrect |
30 ms |
100748 KB |
Output isn't correct |
| 10 |
Correct |
4 ms |
100748 KB |
Output is correct |
| 11 |
Correct |
14 ms |
100748 KB |
Output is correct |
| 12 |
Correct |
3 ms |
100748 KB |
Output is correct |
| 13 |
Incorrect |
1095 ms |
100748 KB |
Output isn't correct |
| 14 |
Incorrect |
475 ms |
100748 KB |
Output isn't correct |
| 15 |
Correct |
24 ms |
100748 KB |
Output is correct |
| 16 |
Incorrect |
1032 ms |
100748 KB |
Output isn't correct |
| 17 |
Execution timed out |
2054 ms |
100748 KB |
Time limit exceeded |
| 18 |
Correct |
117 ms |
100748 KB |
Output is correct |
| 19 |
Execution timed out |
2076 ms |
100748 KB |
Time limit exceeded |
| 20 |
Execution timed out |
2066 ms |
100748 KB |
Time limit exceeded |
| 21 |
Execution timed out |
2057 ms |
100748 KB |
Time limit exceeded |
| 22 |
Correct |
213 ms |
100748 KB |
Output is correct |
| 23 |
Execution timed out |
2067 ms |
100748 KB |
Time limit exceeded |
| 24 |
Correct |
179 ms |
100748 KB |
Output is correct |
| 25 |
Correct |
440 ms |
100748 KB |
Output is correct |
| 26 |
Correct |
971 ms |
100748 KB |
Output is correct |
| 27 |
Incorrect |
1442 ms |
100748 KB |
Output isn't correct |
| 28 |
Execution timed out |
2068 ms |
100748 KB |
Time limit exceeded |
| 29 |
Execution timed out |
2071 ms |
100748 KB |
Time limit exceeded |
| 30 |
Execution timed out |
2063 ms |
100748 KB |
Time limit exceeded |
| 31 |
Execution timed out |
2067 ms |
100748 KB |
Time limit exceeded |
| 32 |
Execution timed out |
2076 ms |
100748 KB |
Time limit exceeded |
