Submission #832673

# Submission time Handle Problem Language Result Execution time Memory
832673 2023-08-21T13:35:54 Z vjudge1 Bomb (IZhO17_bomb) C++14
97 / 100
621 ms 55552 KB
#include<bits/stdc++.h>

#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
using namespace std;

#define ll long long
#define rep(i,n,N) for(int i = n; i<=N; ++i)
#define rap(i,n,N) for(int i = n; i>=N; --i)
#define For(i,n,N) for(int i = n; i< N; ++i)
#define endl '\n'
#define pb push_back
#define all(x) x.begin(),x.end()
#define mems(x,y) memset(x,y,sizeof x)
#define ari(x) array<int,x>
#define pll pair<ll,ll>
#define pii pair<int,int>
#define fi first
#define se second
const int MAX = 2500 + 5;
mt19937 rng(time(NULL));

int n,m,mnr,mnc,cnt,y[MAX][MAX],z[MAX][MAX],ans;
char c;
bool x[MAX][MAX];
vector<ari(3)> v;

inline bool cek(int r,int c,int dr,int dc){
	return y[r][c] - y[r-dr][c] - y[r][c-dc] + y[r-dr][c-dc] == dr*dc;
}

inline bool solve(int dr,int dc){
	rep(i,1,n)mems(z[i], 0);
	rep(i,dr,n)rep(j,dc,m)if(x[i][j] && cek(i,j,dr,dc)){
		z[i][j]++;
		z[i-dr][j]--;
		z[i][j-dc]--;
		z[i-dr][j-dc]++;
	}
	rap(i,n,1)rap(j,m,1){
		z[i][j]+= z[i+1][j]+z[i][j+1]-z[i+1][j+1];
		if((!!z[i][j])!=x[i][j])return 0;
	}
	return 1;
}

int main(){
	ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
	cin>>n>>m;
	mnr = n, mnc = m;
	rep(i,1,n){
		rep(j,1,m){
			cin>>c;
			x[i][j] = c=='1';
			y[i][j] = y[i-1][j]+y[i][j-1]-y[i-1][j-1]+x[i][j];
			if(x[i][j])++cnt;
			else if(cnt)mnc = min(mnc, cnt), cnt = 0;
		}
		if(cnt)mnc = min(mnc, cnt), cnt = 0;
	}
	rep(j,1,m){
		rep(i,1,n){
			if(x[i][j])++cnt;
			else if(cnt)mnr = min(mnr, cnt), cnt = 0;
		}
		if(cnt)mnr = min(mnr, cnt), cnt = 0;
	}
	if(solve(mnr, mnc))return cout<<mnr*mnc<<endl,0;
	if(n*m > 2e6){
		int k = min(mnr, mnc);
		int le,ri,mid;
		le = 1, ri = k;
		while(le<=ri){
			mid = le+ri>>1;
			if(solve(mid, mid))k = mid, le = mid+1;
			else ri = mid-1;
		}
		int r,c;
		r = c = k;
		if(r+1<=mnr && solve(r+1, c)){
			++r;
			le = r+1, ri = mnr;
			while(le<=ri){
				mid = le+ri>>1;
				if(solve(mid, c))r = mid, le = mid+1;
				else ri = mid-1;
			}
		}
		else if(c+1<=mnc){
			le = c+1, ri = mnc;
			while(le<=ri){
				mid = le+ri>>1;
				if(solve(r, mid))c = mid, le = mid+1;
				else ri = mid-1;
			}
		}
		cout<<r*c<<endl;
		return 0;
	}
	ans = mnc;
	rep(i,2,mnr){
		while(i*mnc>ans && !solve(i, mnc))--mnc;
		ans = max(ans, i*mnc);
	}
	cout<<ans<<endl;
	return 0;
}

Compilation message

bomb.cpp: In function 'int main()':
bomb.cpp:74:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   74 |    mid = le+ri>>1;
      |          ~~^~~
bomb.cpp:84:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   84 |     mid = le+ri>>1;
      |           ~~^~~
bomb.cpp:92:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   92 |     mid = le+ri>>1;
      |           ~~^~~
# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 0 ms 596 KB Output is correct
3 Correct 14 ms 40916 KB Output is correct
4 Correct 15 ms 40896 KB Output is correct
5 Correct 0 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 0 ms 596 KB Output is correct
9 Correct 0 ms 596 KB Output is correct
10 Correct 0 ms 468 KB Output is correct
11 Correct 1 ms 596 KB Output is correct
12 Correct 0 ms 596 KB Output is correct
13 Correct 0 ms 596 KB Output is correct
14 Correct 0 ms 596 KB Output is correct
15 Correct 0 ms 596 KB Output is correct
16 Correct 1 ms 596 KB Output is correct
17 Correct 1 ms 1364 KB Output is correct
18 Correct 1 ms 1492 KB Output is correct
19 Correct 1 ms 1876 KB Output is correct
20 Correct 2 ms 1876 KB Output is correct
21 Correct 1 ms 1236 KB Output is correct
22 Correct 1 ms 1492 KB Output is correct
23 Correct 2 ms 2004 KB Output is correct
24 Correct 1 ms 1620 KB Output is correct
25 Correct 2 ms 2004 KB Output is correct
26 Correct 1 ms 2004 KB Output is correct
27 Correct 3 ms 5460 KB Output is correct
28 Correct 9 ms 5620 KB Output is correct
29 Correct 34 ms 7124 KB Output is correct
30 Correct 60 ms 8020 KB Output is correct
31 Correct 43 ms 6356 KB Output is correct
32 Correct 26 ms 7548 KB Output is correct
33 Correct 66 ms 8448 KB Output is correct
34 Correct 9 ms 6468 KB Output is correct
35 Correct 85 ms 8448 KB Output is correct
36 Correct 6 ms 8404 KB Output is correct
37 Correct 0 ms 596 KB Output is correct
38 Correct 97 ms 55380 KB Output is correct
39 Correct 1 ms 596 KB Output is correct
40 Correct 621 ms 17584 KB Output is correct
41 Correct 1 ms 596 KB Output is correct
42 Correct 3 ms 2004 KB Output is correct
43 Correct 102 ms 55372 KB Output is correct
44 Correct 104 ms 8448 KB Output is correct
45 Incorrect 310 ms 55448 KB Output isn't correct
46 Correct 103 ms 55372 KB Output is correct
47 Incorrect 336 ms 55356 KB Output isn't correct
48 Correct 284 ms 55428 KB Output is correct
49 Correct 102 ms 55396 KB Output is correct
50 Correct 329 ms 55528 KB Output is correct
51 Correct 300 ms 55476 KB Output is correct
52 Correct 318 ms 55476 KB Output is correct
53 Correct 305 ms 55416 KB Output is correct
54 Correct 281 ms 55472 KB Output is correct
55 Correct 274 ms 55552 KB Output is correct
56 Correct 100 ms 55444 KB Output is correct
57 Correct 271 ms 55472 KB Output is correct
58 Correct 285 ms 55472 KB Output is correct
59 Correct 269 ms 55468 KB Output is correct
60 Correct 104 ms 55468 KB Output is correct
61 Correct 102 ms 55408 KB Output is correct
62 Correct 106 ms 55432 KB Output is correct
63 Correct 99 ms 55420 KB Output is correct
64 Correct 98 ms 55372 KB Output is correct
65 Correct 263 ms 55360 KB Output is correct
66 Correct 298 ms 55480 KB Output is correct
67 Correct 346 ms 55472 KB Output is correct
68 Correct 359 ms 55472 KB Output is correct
69 Correct 293 ms 55420 KB Output is correct
70 Correct 210 ms 44364 KB Output is correct
71 Correct 351 ms 55500 KB Output is correct
72 Correct 328 ms 55476 KB Output is correct
73 Correct 356 ms 55476 KB Output is correct
74 Correct 367 ms 55472 KB Output is correct
75 Correct 337 ms 55476 KB Output is correct
76 Correct 362 ms 55476 KB Output is correct
77 Correct 378 ms 55476 KB Output is correct
78 Correct 379 ms 55376 KB Output is correct
79 Correct 263 ms 55472 KB Output is correct
80 Correct 253 ms 55476 KB Output is correct
81 Correct 291 ms 55368 KB Output is correct
82 Correct 365 ms 55476 KB Output is correct
83 Correct 363 ms 55452 KB Output is correct
84 Correct 264 ms 55408 KB Output is correct
85 Correct 387 ms 55472 KB Output is correct
86 Correct 315 ms 55464 KB Output is correct
87 Incorrect 342 ms 55372 KB Output isn't correct
88 Correct 348 ms 55348 KB Output is correct
89 Correct 374 ms 55476 KB Output is correct
90 Correct 253 ms 44428 KB Output is correct
91 Correct 401 ms 55472 KB Output is correct
92 Correct 343 ms 55476 KB Output is correct
93 Correct 349 ms 55476 KB Output is correct
94 Correct 372 ms 55468 KB Output is correct
95 Correct 360 ms 55448 KB Output is correct
96 Correct 379 ms 55368 KB Output is correct
97 Correct 322 ms 55372 KB Output is correct
98 Correct 386 ms 55480 KB Output is correct
99 Correct 385 ms 55376 KB Output is correct
100 Correct 339 ms 55388 KB Output is correct