#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];
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
int get_rand(int l, int r){
int tmp = rng()%(r-l+1);
if (tmp < 0) tmp += r-l+1;
return l + tmp;
}
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;
}
}
void solve(int h){
int l = 1, r = W;
while (l <= r){
int mid = (l+r)/2;
if (check(h, mid)){
ans = max(ans, h*mid);
l = mid+1;
}
else{
r = mid-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];
if (N <= 450 && M <= 450){
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;
}
solve(H);
for (int i = 1; i <= 5; i++){
int h = get_rand(1, H);
solve(h);
}
cout << ans;
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4444 KB |
Output is correct |
2 |
Correct |
2 ms |
6492 KB |
Output is correct |
3 |
Correct |
10 ms |
54620 KB |
Output is correct |
4 |
Correct |
9 ms |
54620 KB |
Output is correct |
5 |
Correct |
1 ms |
4444 KB |
Output is correct |
6 |
Correct |
1 ms |
4444 KB |
Output is correct |
7 |
Correct |
1 ms |
4444 KB |
Output is correct |
8 |
Correct |
1 ms |
6492 KB |
Output is correct |
9 |
Correct |
1 ms |
6488 KB |
Output is correct |
10 |
Correct |
1 ms |
4444 KB |
Output is correct |
11 |
Correct |
1 ms |
6492 KB |
Output is correct |
12 |
Correct |
1 ms |
4440 KB |
Output is correct |
13 |
Correct |
1 ms |
4440 KB |
Output is correct |
14 |
Correct |
1 ms |
4444 KB |
Output is correct |
15 |
Correct |
1 ms |
4444 KB |
Output is correct |
16 |
Correct |
1 ms |
6492 KB |
Output is correct |
17 |
Correct |
2 ms |
8796 KB |
Output is correct |
18 |
Correct |
2 ms |
8796 KB |
Output is correct |
19 |
Correct |
3 ms |
10844 KB |
Output is correct |
20 |
Correct |
3 ms |
10844 KB |
Output is correct |
21 |
Correct |
2 ms |
6748 KB |
Output is correct |
22 |
Correct |
2 ms |
10844 KB |
Output is correct |
23 |
Correct |
4 ms |
10844 KB |
Output is correct |
24 |
Correct |
3 ms |
10892 KB |
Output is correct |
25 |
Correct |
4 ms |
10896 KB |
Output is correct |
26 |
Correct |
3 ms |
10844 KB |
Output is correct |
27 |
Correct |
4 ms |
15192 KB |
Output is correct |
28 |
Correct |
8 ms |
13148 KB |
Output is correct |
29 |
Correct |
52 ms |
14940 KB |
Output is correct |
30 |
Correct |
134 ms |
14940 KB |
Output is correct |
31 |
Correct |
81 ms |
13404 KB |
Output is correct |
32 |
Correct |
90 ms |
14976 KB |
Output is correct |
33 |
Correct |
173 ms |
17156 KB |
Output is correct |
34 |
Correct |
7 ms |
13400 KB |
Output is correct |
35 |
Correct |
59 ms |
16224 KB |
Output is correct |
36 |
Correct |
52 ms |
19036 KB |
Output is correct |
37 |
Correct |
2 ms |
6492 KB |
Output is correct |
38 |
Execution timed out |
1088 ms |
55708 KB |
Time limit exceeded |
39 |
Correct |
1 ms |
6488 KB |
Output is correct |
40 |
Incorrect |
131 ms |
27292 KB |
Output isn't correct |
41 |
Correct |
2 ms |
6488 KB |
Output is correct |
42 |
Correct |
5 ms |
10844 KB |
Output is correct |
43 |
Execution timed out |
1059 ms |
55452 KB |
Time limit exceeded |
44 |
Correct |
244 ms |
19284 KB |
Output is correct |
45 |
Execution timed out |
1073 ms |
55452 KB |
Time limit exceeded |
46 |
Correct |
914 ms |
55440 KB |
Output is correct |
47 |
Execution timed out |
1067 ms |
55636 KB |
Time limit exceeded |
48 |
Execution timed out |
1058 ms |
55620 KB |
Time limit exceeded |
49 |
Correct |
607 ms |
55872 KB |
Output is correct |
50 |
Execution timed out |
1018 ms |
55632 KB |
Time limit exceeded |
51 |
Execution timed out |
1026 ms |
55428 KB |
Time limit exceeded |
52 |
Execution timed out |
1024 ms |
55440 KB |
Time limit exceeded |
53 |
Execution timed out |
1066 ms |
55636 KB |
Time limit exceeded |
54 |
Execution timed out |
1099 ms |
55632 KB |
Time limit exceeded |
55 |
Execution timed out |
1025 ms |
55632 KB |
Time limit exceeded |
56 |
Execution timed out |
1018 ms |
55664 KB |
Time limit exceeded |
57 |
Execution timed out |
1026 ms |
55456 KB |
Time limit exceeded |
58 |
Execution timed out |
1070 ms |
55452 KB |
Time limit exceeded |
59 |
Execution timed out |
1076 ms |
55440 KB |
Time limit exceeded |
60 |
Execution timed out |
1010 ms |
55656 KB |
Time limit exceeded |
61 |
Execution timed out |
1010 ms |
55660 KB |
Time limit exceeded |
62 |
Execution timed out |
1025 ms |
55632 KB |
Time limit exceeded |
63 |
Execution timed out |
1053 ms |
55636 KB |
Time limit exceeded |
64 |
Execution timed out |
1041 ms |
55820 KB |
Time limit exceeded |
65 |
Execution timed out |
1034 ms |
55656 KB |
Time limit exceeded |
66 |
Execution timed out |
1039 ms |
55432 KB |
Time limit exceeded |
67 |
Execution timed out |
1094 ms |
55636 KB |
Time limit exceeded |
68 |
Execution timed out |
1033 ms |
55612 KB |
Time limit exceeded |
69 |
Execution timed out |
1080 ms |
55448 KB |
Time limit exceeded |
70 |
Incorrect |
708 ms |
49864 KB |
Output isn't correct |
71 |
Incorrect |
901 ms |
55664 KB |
Output isn't correct |
72 |
Execution timed out |
1078 ms |
55448 KB |
Time limit exceeded |
73 |
Execution timed out |
1072 ms |
55636 KB |
Time limit exceeded |
74 |
Execution timed out |
1067 ms |
55664 KB |
Time limit exceeded |
75 |
Execution timed out |
1024 ms |
55444 KB |
Time limit exceeded |
76 |
Execution timed out |
1020 ms |
55632 KB |
Time limit exceeded |
77 |
Incorrect |
951 ms |
55656 KB |
Output isn't correct |
78 |
Execution timed out |
1044 ms |
55660 KB |
Time limit exceeded |
79 |
Incorrect |
556 ms |
55660 KB |
Output isn't correct |
80 |
Incorrect |
543 ms |
55664 KB |
Output isn't correct |
81 |
Incorrect |
906 ms |
55656 KB |
Output isn't correct |
82 |
Incorrect |
950 ms |
55664 KB |
Output isn't correct |
83 |
Execution timed out |
1073 ms |
55428 KB |
Time limit exceeded |
84 |
Incorrect |
662 ms |
55668 KB |
Output isn't correct |
85 |
Execution timed out |
1012 ms |
55660 KB |
Time limit exceeded |
86 |
Incorrect |
639 ms |
55660 KB |
Output isn't correct |
87 |
Execution timed out |
1081 ms |
55660 KB |
Time limit exceeded |
88 |
Execution timed out |
1094 ms |
55440 KB |
Time limit exceeded |
89 |
Execution timed out |
1041 ms |
55888 KB |
Time limit exceeded |
90 |
Incorrect |
630 ms |
49744 KB |
Output isn't correct |
91 |
Incorrect |
855 ms |
55888 KB |
Output isn't correct |
92 |
Incorrect |
875 ms |
55656 KB |
Output isn't correct |
93 |
Incorrect |
667 ms |
55656 KB |
Output isn't correct |
94 |
Incorrect |
966 ms |
55664 KB |
Output isn't correct |
95 |
Execution timed out |
1008 ms |
55460 KB |
Time limit exceeded |
96 |
Execution timed out |
1064 ms |
55636 KB |
Time limit exceeded |
97 |
Incorrect |
817 ms |
55660 KB |
Output isn't correct |
98 |
Execution timed out |
1016 ms |
55792 KB |
Time limit exceeded |
99 |
Execution timed out |
1018 ms |
55632 KB |
Time limit exceeded |
100 |
Incorrect |
630 ms |
55676 KB |
Output isn't correct |