#include <bits/stdc++.h>
using namespace std;
const int NM = 2500, inf = 1e9+7;
int N, M, f[NM+5][NM+5], dp[NM+5][NM+5], ans = 0, H = +inf, W = +inf;
char a[NM+5][NM+5];
int getf(int x, int y, int u, int v){
return f[u][v]-f[x-1][v]-f[u][y-1]+f[x-1][y-1];
}
bool check(int r, int c){
for (int i = 1; i <= N; i++)
for (int j = 1; j <= M; j++) dp[i][j] = 0;
for (int i = 1; i+r-1 <= N; i++)
for (int j = 1; j+c-1 <= M; j++)
if (getf(i, j, i+r-1, j+c-1) == r*c){
dp[i][j]++;
dp[i+r][j]--;
dp[i][j+c]--;
dp[i+r][j+c]++;
}
for (int i = 1; i <= N; i++)
for (int j = 1; j <= M; j++){
dp[i][j] += dp[i-1][j]+dp[i][j-1]-dp[i-1][j-1];
if (dp[i][j] == 0 && a[i][j] == '1') return 0;
}
return 1;
}
void preprocess(){
for (int j = 1; j <= M; j++)
for (int i = 1; i <= N; i++){
if (a[i][j] == '0') continue;
int k = i;
while (k <= N && a[k][j] == '1') k++;
H = min(H, k-i);
i = k-1;
}
for (int i = 1; i <= N; i++)
for (int j = 1; j <= M; j++){
if (a[i][j] == '0') continue;
int k = j;
while (k <= M && a[i][k] == '1') k++;
W = min(W, k-j);
j = k-1;
}
}
int main(){
// freopen("BOMB.inp", "r", stdin);
// freopen("BOMB.ans", "w", stdout);
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
cin >> N >> M;
for (int i = 1; i <= N; i++)
for (int j = 1; j <= M; j++){
cin >> a[i][j];
if (a[i][j] == '1') f[i][j] = 1;
}
preprocess();
for (int i = 1; i <= N; i++)
for (int j = 1; j <= M; j++)
f[i][j] += f[i][j-1]+f[i-1][j]-f[i-1][j-1];
int j = W;
for (int i = 1; i <= H; i++){
while (j >= 0 && !check(i, j)) j--;
ans = max(ans, i*j);
}
cout << ans;
return 0;
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
2 ms |
4444 KB |
Output is correct |
| 2 |
Correct |
2 ms |
4444 KB |
Output is correct |
| 3 |
Correct |
12 ms |
54620 KB |
Output is correct |
| 4 |
Correct |
13 ms |
54620 KB |
Output is correct |
| 5 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 6 |
Correct |
2 ms |
4440 KB |
Output is correct |
| 7 |
Correct |
2 ms |
4444 KB |
Output is correct |
| 8 |
Correct |
2 ms |
4440 KB |
Output is correct |
| 9 |
Correct |
2 ms |
4444 KB |
Output is correct |
| 10 |
Correct |
1 ms |
4440 KB |
Output is correct |
| 11 |
Correct |
2 ms |
4440 KB |
Output is correct |
| 12 |
Correct |
2 ms |
4444 KB |
Output is correct |
| 13 |
Correct |
2 ms |
4444 KB |
Output is correct |
| 14 |
Correct |
2 ms |
4444 KB |
Output is correct |
| 15 |
Correct |
2 ms |
4444 KB |
Output is correct |
| 16 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 17 |
Correct |
2 ms |
8796 KB |
Output is correct |
| 18 |
Correct |
3 ms |
8796 KB |
Output is correct |
| 19 |
Correct |
4 ms |
10840 KB |
Output is correct |
| 20 |
Correct |
3 ms |
10840 KB |
Output is correct |
| 21 |
Correct |
2 ms |
6748 KB |
Output is correct |
| 22 |
Correct |
3 ms |
10844 KB |
Output is correct |
| 23 |
Correct |
4 ms |
10844 KB |
Output is correct |
| 24 |
Correct |
4 ms |
10840 KB |
Output is correct |
| 25 |
Correct |
5 ms |
10844 KB |
Output is correct |
| 26 |
Correct |
4 ms |
10844 KB |
Output is correct |
| 27 |
Correct |
5 ms |
14936 KB |
Output is correct |
| 28 |
Correct |
10 ms |
15008 KB |
Output is correct |
| 29 |
Correct |
58 ms |
14984 KB |
Output is correct |
| 30 |
Correct |
132 ms |
14992 KB |
Output is correct |
| 31 |
Correct |
88 ms |
14980 KB |
Output is correct |
| 32 |
Correct |
90 ms |
14936 KB |
Output is correct |
| 33 |
Correct |
184 ms |
17072 KB |
Output is correct |
| 34 |
Correct |
9 ms |
13400 KB |
Output is correct |
| 35 |
Correct |
62 ms |
16988 KB |
Output is correct |
| 36 |
Correct |
53 ms |
19032 KB |
Output is correct |
| 37 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 38 |
Execution timed out |
1079 ms |
55636 KB |
Time limit exceeded |
| 39 |
Correct |
1 ms |
6744 KB |
Output is correct |
| 40 |
Execution timed out |
1068 ms |
27228 KB |
Time limit exceeded |
| 41 |
Correct |
2 ms |
6488 KB |
Output is correct |
| 42 |
Correct |
5 ms |
10844 KB |
Output is correct |
| 43 |
Execution timed out |
1090 ms |
55436 KB |
Time limit exceeded |
| 44 |
Correct |
238 ms |
19084 KB |
Output is correct |
| 45 |
Execution timed out |
1077 ms |
55636 KB |
Time limit exceeded |
| 46 |
Correct |
845 ms |
55852 KB |
Output is correct |
| 47 |
Execution timed out |
1029 ms |
55448 KB |
Time limit exceeded |
| 48 |
Execution timed out |
1026 ms |
55636 KB |
Time limit exceeded |
| 49 |
Correct |
293 ms |
55652 KB |
Output is correct |
| 50 |
Execution timed out |
1051 ms |
55448 KB |
Time limit exceeded |
| 51 |
Execution timed out |
1048 ms |
55712 KB |
Time limit exceeded |
| 52 |
Execution timed out |
1038 ms |
55632 KB |
Time limit exceeded |
| 53 |
Execution timed out |
1029 ms |
55584 KB |
Time limit exceeded |
| 54 |
Execution timed out |
1022 ms |
55448 KB |
Time limit exceeded |
| 55 |
Execution timed out |
1052 ms |
55452 KB |
Time limit exceeded |
| 56 |
Execution timed out |
1024 ms |
55632 KB |
Time limit exceeded |
| 57 |
Execution timed out |
1051 ms |
55700 KB |
Time limit exceeded |
| 58 |
Execution timed out |
1002 ms |
55632 KB |
Time limit exceeded |
| 59 |
Execution timed out |
1061 ms |
55636 KB |
Time limit exceeded |
| 60 |
Correct |
976 ms |
55656 KB |
Output is correct |
| 61 |
Correct |
632 ms |
55656 KB |
Output is correct |
| 62 |
Execution timed out |
1063 ms |
55636 KB |
Time limit exceeded |
| 63 |
Execution timed out |
1030 ms |
55632 KB |
Time limit exceeded |
| 64 |
Execution timed out |
1049 ms |
55632 KB |
Time limit exceeded |
| 65 |
Execution timed out |
1062 ms |
55636 KB |
Time limit exceeded |
| 66 |
Correct |
438 ms |
55660 KB |
Output is correct |
| 67 |
Execution timed out |
1057 ms |
55640 KB |
Time limit exceeded |
| 68 |
Execution timed out |
1022 ms |
55632 KB |
Time limit exceeded |
| 69 |
Execution timed out |
1010 ms |
55632 KB |
Time limit exceeded |
| 70 |
Execution timed out |
1069 ms |
49748 KB |
Time limit exceeded |
| 71 |
Execution timed out |
1025 ms |
55452 KB |
Time limit exceeded |
| 72 |
Execution timed out |
1031 ms |
55632 KB |
Time limit exceeded |
| 73 |
Execution timed out |
1056 ms |
55448 KB |
Time limit exceeded |
| 74 |
Execution timed out |
1012 ms |
55632 KB |
Time limit exceeded |
| 75 |
Execution timed out |
1045 ms |
55636 KB |
Time limit exceeded |
| 76 |
Execution timed out |
1055 ms |
55452 KB |
Time limit exceeded |
| 77 |
Execution timed out |
1057 ms |
55640 KB |
Time limit exceeded |
| 78 |
Execution timed out |
1029 ms |
55636 KB |
Time limit exceeded |
| 79 |
Execution timed out |
1025 ms |
55424 KB |
Time limit exceeded |
| 80 |
Execution timed out |
1039 ms |
55636 KB |
Time limit exceeded |
| 81 |
Execution timed out |
1038 ms |
55432 KB |
Time limit exceeded |
| 82 |
Execution timed out |
1064 ms |
55636 KB |
Time limit exceeded |
| 83 |
Execution timed out |
1062 ms |
55636 KB |
Time limit exceeded |
| 84 |
Execution timed out |
1027 ms |
55684 KB |
Time limit exceeded |
| 85 |
Execution timed out |
1030 ms |
55632 KB |
Time limit exceeded |
| 86 |
Execution timed out |
1032 ms |
55632 KB |
Time limit exceeded |
| 87 |
Execution timed out |
1035 ms |
55632 KB |
Time limit exceeded |
| 88 |
Execution timed out |
1101 ms |
55632 KB |
Time limit exceeded |
| 89 |
Execution timed out |
1047 ms |
55452 KB |
Time limit exceeded |
| 90 |
Execution timed out |
1012 ms |
49828 KB |
Time limit exceeded |
| 91 |
Execution timed out |
1030 ms |
55516 KB |
Time limit exceeded |
| 92 |
Execution timed out |
1030 ms |
55444 KB |
Time limit exceeded |
| 93 |
Execution timed out |
1035 ms |
55636 KB |
Time limit exceeded |
| 94 |
Execution timed out |
1048 ms |
55648 KB |
Time limit exceeded |
| 95 |
Execution timed out |
1020 ms |
55472 KB |
Time limit exceeded |
| 96 |
Execution timed out |
1045 ms |
55484 KB |
Time limit exceeded |
| 97 |
Execution timed out |
1051 ms |
55636 KB |
Time limit exceeded |
| 98 |
Execution timed out |
1034 ms |
55580 KB |
Time limit exceeded |
| 99 |
Execution timed out |
1085 ms |
55868 KB |
Time limit exceeded |
| 100 |
Execution timed out |
1042 ms |
55440 KB |
Time limit exceeded |
