oj.uz

Submission #697255

# Submission time Handle Problem Language Result Execution time Memory
697255 2023-02-09T01:21:39 Z allllekssssa Bomb (IZhO17_bomb) C++14
57 / 100
 1000 ms 78436 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(400, (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
57.0 / 100.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 468 KB Output is correct
3 Correct 16 ms 30452 KB Output is correct
4 Correct 23 ms 30420 KB Output is correct
5 Correct 1 ms 312 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 1 ms 308 KB Output is correct
8 Correct 1 ms 572 KB Output is correct
9 Correct 1 ms 568 KB Output is correct
10 Correct 1 ms 468 KB Output is correct
11 Correct 1 ms 468 KB Output is correct
12 Correct 1 ms 440 KB Output is correct
13 Correct 1 ms 468 KB Output is correct
14 Correct 1 ms 480 KB Output is correct
15 Correct 1 ms 468 KB Output is correct
16 Correct 1 ms 468 KB Output is correct
17 Correct 5 ms 1108 KB Output is correct
18 Correct 4 ms 1108 KB Output is correct
19 Correct 10 ms 1492 KB Output is correct
20 Correct 7 ms 1468 KB Output is correct
21 Correct 5 ms 980 KB Output is correct
22 Correct 6 ms 1216 KB Output is correct
23 Correct 10 ms 1620 KB Output is correct
24 Correct 6 ms 1336 KB Output is correct
25 Correct 13 ms 1748 KB Output is correct
26 Correct 9 ms 1596 KB Output is correct
27 Correct 173 ms 4848 KB Output is correct
28 Correct 310 ms 5200 KB Output is correct
29 Correct 374 ms 6580 KB Output is correct
30 Correct 817 ms 7892 KB Output is correct
31 Correct 619 ms 6224 KB Output is correct
32 Correct 552 ms 7152 KB Output is correct
33 Correct 993 ms 8284 KB Output is correct
34 Correct 124 ms 5604 KB Output is correct
35 Correct 650 ms 8284 KB Output is correct
36 Correct 802 ms 8280 KB Output is correct
37 Correct 1 ms 564 KB Output is correct
38 Correct 319 ms 78328 KB Output is correct
39 Correct 1 ms 468 KB Output is correct
40 Incorrect 34 ms 20464 KB Output isn't correct
41 Correct 1 ms 568 KB Output is correct
42 Correct 13 ms 1620 KB Output is correct
43 Correct 403 ms 78420 KB Output is correct
44 Execution timed out 1079 ms 8240 KB Time limit exceeded
45 Incorrect 478 ms 78352 KB Output isn't correct
46 Correct 373 ms 78136 KB Output is correct
47 Incorrect 415 ms 78412 KB Output isn't correct
48 Correct 372 ms 78368 KB Output is correct
49 Correct 356 ms 78416 KB Output is correct
50 Incorrect 351 ms 78436 KB Output isn't correct
51 Incorrect 440 ms 76644 KB Output isn't correct
52 Correct 355 ms 76628 KB Output is correct
53 Incorrect 336 ms 76616 KB Output isn't correct
54 Correct 409 ms 76644 KB Output is correct
55 Incorrect 343 ms 76532 KB Output isn't correct
56 Correct 309 ms 76632 KB Output is correct
57 Incorrect 359 ms 76612 KB Output isn't correct
58 Incorrect 359 ms 76588 KB Output isn't correct
59 Correct 335 ms 76648 KB Output is correct
60 Correct 292 ms 76628 KB Output is correct
61 Correct 349 ms 76756 KB Output is correct
62 Correct 308 ms 76632 KB Output is correct
63 Correct 340 ms 76600 KB Output is correct
64 Correct 291 ms 76544 KB Output is correct
65 Correct 333 ms 76636 KB Output is correct
66 Incorrect 314 ms 76520 KB Output isn't correct
67 Correct 321 ms 76644 KB Output is correct
68 Incorrect 337 ms 76640 KB Output isn't correct
69 Correct 332 ms 76632 KB Output is correct
70 Incorrect 203 ms 61368 KB Output isn't correct
71 Incorrect 273 ms 76732 KB Output isn't correct
72 Incorrect 277 ms 76528 KB Output isn't correct
73 Incorrect 291 ms 76548 KB Output isn't correct
74 Incorrect 283 ms 76640 KB Output isn't correct
75 Incorrect 274 ms 76872 KB Output isn't correct
76 Incorrect 343 ms 76676 KB Output isn't correct
77 Incorrect 286 ms 76596 KB Output isn't correct
78 Incorrect 315 ms 76652 KB Output isn't correct
79 Incorrect 300 ms 76528 KB Output isn't correct
80 Incorrect 278 ms 76632 KB Output isn't correct
81 Incorrect 311 ms 76636 KB Output isn't correct
82 Incorrect 286 ms 76648 KB Output isn't correct
83 Incorrect 292 ms 76564 KB Output isn't correct
84 Incorrect 289 ms 76620 KB Output isn't correct
85 Incorrect 309 ms 76580 KB Output isn't correct
86 Incorrect 274 ms 76632 KB Output isn't correct
87 Incorrect 298 ms 76596 KB Output isn't correct
88 Incorrect 272 ms 76536 KB Output isn't correct
89 Incorrect 284 ms 76536 KB Output isn't correct
90 Incorrect 205 ms 61368 KB Output isn't correct
91 Incorrect 275 ms 76612 KB Output isn't correct
92 Incorrect 301 ms 76524 KB Output isn't correct
93 Incorrect 271 ms 76528 KB Output isn't correct
94 Incorrect 277 ms 76660 KB Output isn't correct
95 Incorrect 283 ms 76536 KB Output isn't correct
96 Incorrect 288 ms 76628 KB Output isn't correct
97 Incorrect 284 ms 76516 KB Output isn't correct
98 Incorrect 270 ms 76532 KB Output isn't correct
99 Incorrect 275 ms 76620 KB Output isn't correct
100 Incorrect 271 ms 76528 KB Output isn't correct