oj.uz

Submission #697260

# Submission time Handle Problem Language Result Execution time Memory
697260 2023-02-09T01:25:17 Z allllekssssa Bomb (IZhO17_bomb) C++14
59 / 100
 931 ms 76712 KB 
#include<bits/stdc++.h>
 
using namespace std;


#define pii pair<int ,int>
#define pb push_back

const int maxN = 2600;
int n, m;
int a[maxN][maxN];
int d[maxN][maxN];
int c[maxN][maxN];
string s;
int cnt[maxN];

int getDSum(int x1, int y1, int x2, int y2) {
	if (x2 > n || y2 > m) return 0;
	return d[x2][y2] + d[x1 - 1][y1 - 1] - d[x1 - 1][y2] - d[x2][y1 - 1];
}
 
int getCSum(int x1, int y1, int x2, int y2) {
	x1 = max(x1, 1);
	y1 = max(y1, 1);
	return c[x2][y2] + c[x1 - 1][y1 - 1] - c[x1 - 1][y2] - c[x2][y1 - 1];
}
 
bool check(int x, int y) {
 
	for (int i = 1; i<=n; i++) {
		for (int j = 1; j<=m; j++) {
			c[i][j] = 0;
		}
	}
   
   for (int i = 1; i<=n; i++) {
   	 for (int j = 1; j<=m; j++) {
   	 	if (getDSum(i, j, i + x - 1, j + y - 1) == x * y) c[i][j] = 1;
   	 }
   }
 
   for (int i = 1; i <= n; i++) {
		for (int j = 1; j<=m; j++) {
			c[i][j] += c[i - 1][j] + c[i][j - 1] - c[i - 1][j - 1];
		}
	}
 
   for (int i = 1; i<=n; i++) {
   	for (int j = 1; j <= m; j++) {
 		  if (a[i][j] && getCSum(i - x + 1, j - y + 1, i, j) == 0) return false;
   	  }
   }
 
   return true;
}

int heuristic1() {
    
	vector<pii> gornji;

	for (int i = 1; i<=n; i++) {
		for (int j = 1; j<=m; j++) {
			if (a[i - 1][j] == 0 && a[i][j - 1] == 0 && a[i][j] == 1) gornji.pb({i, j});
		}
	}

	random_shuffle(gornji.begin(), gornji.end());
    
    for (int i = 1; i <=n; i++) {
    	cnt[i] = m;
    }

    for (int i = 0; i < min(1400, (int) gornji.size()); i++) {
       for (int len = 1; len <= n; len++) {
          
          int x = gornji[i].first;
          int y = gornji[i].second;

       	  int lo = -1;
       	  int ro = m + 1;
 
       	  while(lo < ro - 1) {
       	  	 int mid = lo + ro >> 1;
       	  	 if (getDSum(x, y, x + len - 1, y + mid - 1) == len * mid) lo = mid; else ro = mid;
       	  }

       	  cnt[len] = min(cnt[len], lo);
       }
    }


    int ans = 0;
    for (int i = 1; i<=n; i++) {
    	ans = max(ans, i * cnt[i]);
    }

    return ans;
}
 
int heuristic() {
  
   int minW = n;
   int minH = m;

	for (int i = 1; i<=n; i++) {
		int cur = 0;
		for (int j = 1; j<=m; j++) {
			if (a[i][j] == 1) cur++; else {
				if (cur > 0) {
					minH = min(minH, cur);
					cur = 0;
				}
			}
		}

	   if (cur > 0) minH = min(minH, cur);
	}

	for (int j = 1; j<=m; j++) {
		int cur = 0;
		for (int i = 1; i<=n; i++) {
			if (a[i][j] == 1) cur++; else {
				if (cur > 0) {
					minW = min(minW, cur);
					cur = 0;
				}
			}
		}

		if (cur > 0) minW = min(minW, cur);
	}
    
    int ans = minW * minH;
    if (!check(minW, minH)) return heuristic1();
	return ans;
}

int main() {
 
	cin >> n >> m;
 
	for (int i = 1; i <=n; i++) {
		cin >> s;
 
		for (int j = 0; j < m; j++) {
			a[i][j + 1] = s[j] - '0';
		}
	}
    
    for (int i = 1; i <= n; i++) {
		for (int j = 1; j<=m; j++) {
			d[i][j] = d[i - 1][j] + d[i][j - 1] + a[i][j] - d[i - 1][j - 1];
		}
	}

	if (n > 450 || m > 450) {
		cout << heuristic() << endl;
		return 0;
	}

   
    int ans = 0;
    
    int width = m;
	for (int i = 1; i <=n; i++) {
 
		while (width > 0 && !check(i, width)) width--;
 
		ans = max(ans, i * width);
	}
    
    cout << ans << endl;
}

Compilation message

bomb.cpp: In function 'int heuristic1()':
bomb.cpp:83:26: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   83 |             int mid = lo + ro >> 1;
      |                       ~~~^~~~

Subtask #1
59.0 / 100.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 1 ms 468 KB Output is correct
3 Correct 14 ms 30440 KB Output is correct
4 Correct 13 ms 30396 KB Output is correct
5 Correct 1 ms 340 KB Output is correct
6 Correct 0 ms 340 KB Output is correct
7 Correct 0 ms 340 KB Output is correct
8 Correct 1 ms 468 KB Output is correct
9 Correct 1 ms 468 KB Output is correct
10 Correct 0 ms 468 KB Output is correct
11 Correct 1 ms 468 KB Output is correct
12 Correct 0 ms 468 KB Output is correct
13 Correct 0 ms 468 KB Output is correct
14 Correct 0 ms 468 KB Output is correct
15 Correct 1 ms 468 KB Output is correct
16 Correct 1 ms 468 KB Output is correct
17 Correct 4 ms 1108 KB Output is correct
18 Correct 3 ms 1108 KB Output is correct
19 Correct 5 ms 1492 KB Output is correct
20 Correct 5 ms 1492 KB Output is correct
21 Correct 3 ms 980 KB Output is correct
22 Correct 5 ms 1320 KB Output is correct
23 Correct 11 ms 1620 KB Output is correct
24 Correct 4 ms 1364 KB Output is correct
25 Correct 10 ms 1620 KB Output is correct
26 Correct 10 ms 1620 KB Output is correct
27 Correct 130 ms 4768 KB Output is correct
28 Correct 247 ms 5200 KB Output is correct
29 Correct 315 ms 6444 KB Output is correct
30 Correct 622 ms 7700 KB Output is correct
31 Correct 470 ms 6100 KB Output is correct
32 Correct 470 ms 6996 KB Output is correct
33 Correct 740 ms 8092 KB Output is correct
34 Correct 114 ms 5520 KB Output is correct
35 Correct 556 ms 8088 KB Output is correct
36 Correct 679 ms 8088 KB Output is correct
37 Correct 1 ms 468 KB Output is correct
38 Correct 265 ms 76620 KB Output is correct
39 Correct 0 ms 468 KB Output is correct
40 Incorrect 33 ms 19880 KB Output isn't correct
41 Correct 0 ms 468 KB Output is correct
42 Correct 11 ms 1748 KB Output is correct
43 Correct 268 ms 76636 KB Output is correct
44 Correct 931 ms 8088 KB Output is correct
45 Incorrect 407 ms 76644 KB Output isn't correct
46 Correct 267 ms 76584 KB Output is correct
47 Incorrect 411 ms 76640 KB Output isn't correct
48 Correct 287 ms 76632 KB Output is correct
49 Correct 280 ms 76524 KB Output is correct
50 Incorrect 301 ms 76632 KB Output isn't correct
51 Incorrect 307 ms 76700 KB Output isn't correct
52 Correct 291 ms 76604 KB Output is correct
53 Incorrect 289 ms 76592 KB Output isn't correct
54 Correct 382 ms 76576 KB Output is correct
55 Incorrect 300 ms 76660 KB Output isn't correct
56 Correct 275 ms 76624 KB Output is correct
57 Incorrect 308 ms 76640 KB Output isn't correct
58 Correct 308 ms 76540 KB Output is correct
59 Correct 307 ms 76612 KB Output is correct
60 Correct 261 ms 76508 KB Output is correct
61 Correct 274 ms 76528 KB Output is correct
62 Correct 268 ms 76632 KB Output is correct
63 Correct 272 ms 76712 KB Output is correct
64 Correct 257 ms 76636 KB Output is correct
65 Correct 285 ms 76532 KB Output is correct
66 Incorrect 271 ms 76676 KB Output isn't correct
67 Correct 303 ms 76640 KB Output is correct
68 Incorrect 304 ms 76668 KB Output isn't correct
69 Correct 289 ms 76596 KB Output is correct
70 Incorrect 183 ms 61368 KB Output isn't correct
71 Incorrect 277 ms 76696 KB Output isn't correct
72 Incorrect 266 ms 76572 KB Output isn't correct
73 Incorrect 266 ms 76552 KB Output isn't correct
74 Incorrect 269 ms 76660 KB Output isn't correct
75 Incorrect 267 ms 76568 KB Output isn't correct
76 Incorrect 266 ms 76560 KB Output isn't correct
77 Incorrect 271 ms 76612 KB Output isn't correct
78 Incorrect 266 ms 76632 KB Output isn't correct
79 Incorrect 275 ms 76616 KB Output isn't correct
80 Incorrect 268 ms 76616 KB Output isn't correct
81 Incorrect 277 ms 76568 KB Output isn't correct
82 Incorrect 283 ms 76632 KB Output isn't correct
83 Incorrect 264 ms 76620 KB Output isn't correct
84 Incorrect 261 ms 76620 KB Output isn't correct
85 Incorrect 265 ms 76584 KB Output isn't correct
86 Incorrect 265 ms 76572 KB Output isn't correct
87 Incorrect 285 ms 76528 KB Output isn't correct
88 Incorrect 267 ms 76632 KB Output isn't correct
89 Incorrect 271 ms 76588 KB Output isn't correct
90 Incorrect 181 ms 61312 KB Output isn't correct
91 Incorrect 265 ms 76620 KB Output isn't correct
92 Incorrect 267 ms 76620 KB Output isn't correct
93 Incorrect 264 ms 76548 KB Output isn't correct
94 Incorrect 281 ms 76552 KB Output isn't correct
95 Incorrect 286 ms 76580 KB Output isn't correct
96 Incorrect 283 ms 76620 KB Output isn't correct
97 Incorrect 261 ms 76624 KB Output isn't correct
98 Incorrect 283 ms 76532 KB Output isn't correct
99 Incorrect 265 ms 76632 KB Output isn't correct
100 Incorrect 270 ms 76528 KB Output isn't correct