Submission #831262

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
831262	2023-08-20T03:07:13 Z	vjudge1	Bomb (IZhO17_bomb)	C++17	100 / 100	312 ms	55992 KB

bomb

// 赤コーダーになりたい
// お願い いいですか？

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

// Pragmas
// #pragma GCC optimize("Ofast")
// #pragma GCC optimize("unroll-loops")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")

// Namespaces
using namespace std;
using namespace __gnu_pbds;

// Data types
using si	= short int;
using ll	= long long;
using lll	= __int128;
using ld	= long double;

// Pairs
using pii	= pair<int, int>;
using psi	= pair<si, si>;
using pll	= pair<ll, ll>;
using plll	= pair<lll, lll>;
using pld	= pair<ld, ld>;
#define fi	first
#define se	second

// For
#define Frue(i, n, N)		for (int i = (n); i <= (N); i++)
#define  Fru(i, n, N)		for (int i = (n); i <  (N); i++)
#define Frde(i, n, N)		for (int i = (n); i >= (N); i--)
#define  Frd(i, n, N)		for (int i = (n); i >  (N); i--)

// PBDS
template<typename Z>
using ordered_set	= tree<Z, null_type, less<Z>, rb_tree_tag, tree_order_statistics_node_update>;

// Various outputs
template<typename Y, typename Z> ostream& operator<<(ostream &os, const pair<Y, Z> &p) {
	return os << '(' << p.fi << ',' << p.se << ')';
}
template<typename Z> ostream& operator<<(ostream &os, const vector<Z> &v) {
	os << '{'; bool _first = 1;
	for (auto &i : v) {if (!_first) os << ", "; os << i; _first = 0;}
	return os << '}';
}
template<typename Z, unsigned long long sz> ostream& operator<<(ostream &os, const array<Z, sz> &arr) {
	os << '{'; bool _first = 1;
	for (auto &i : arr) {if (!_first) os << ", "; os << i; _first = 0;}
	return os << '}';
}

// Quick macro functions
#define sqr(x)			((x)*(x))
#define debug(x)		cout << #x << " = " << (x) << '\n'
#define debugV(v, x)	cout << #v << "[" << (x) << "] = " << (v[x]) << '\n'
#define rrebug(x)		cerr << #x << " = " << (x) << '\n'
#define rrebugV(v, x)	cerr << #v << "[" << (x) << "] = " << (v[x]) << '\n'

#define All(x)			x.begin(), x.end()
#define Sort(x)			sort(All(x))
#define Reverse(x)		reverse(All(x))
#define Uniqueify(x)	Sort(x); x.erase(unique(All(x)), x.end())

#define RandomSeed			chrono::steady_clock::now().time_since_epoch().count()
#define MultipleTestcases	int _tc; cin >> _tc; for (int _cur_tc = 1; _cur_tc <= _tc; _cur_tc++)

// Check min and max
template<typename Z> void chmin(Z &a, Z b) {a = min(a, b);}
template<typename Z> void chmax(Z &a, Z b) {a = max(a, b);}
 
// Modular arithmetic
template<int MOD>
class ModInt {
  public:
	int v;
	ModInt() : v(0) {}
	ModInt(long long _v) {
		v = int((-MOD < _v && _v < MOD) ? (_v) : (_v % MOD));
		if (v < 0) v += MOD;
	}
 
	friend bool operator==(const ModInt &a, const ModInt &b) {return a.v == b.v;}
	friend bool operator!=(const ModInt &a, const ModInt &b) {return a.v != b.v;}
	friend bool operator< (const ModInt &a, const ModInt &b) {return a.v <  b.v;}
	friend bool operator<=(const ModInt &a, const ModInt &b) {return a.v <= b.v;}
	friend bool operator> (const ModInt &a, const ModInt &b) {return a.v >  b.v;}
	friend bool operator>=(const ModInt &a, const ModInt &b) {return a.v >= b.v;}
 
	ModInt &operator+=(const ModInt &a) {if ((v += a.v) >= MOD) v -= MOD; return *this;}
	ModInt &operator-=(const ModInt &a) {if ((v -= a.v) < 0) v += MOD; return *this;}
	ModInt &operator*=(const ModInt &a) {v = 1ll * v * a.v % MOD; return *this;}
	ModInt &operator/=(const ModInt &a) {return (*this) *= inverse(a);}
 
	friend ModInt pow(ModInt a, long long x) {
		ModInt res = 1;
		for (; x; x /= 2, a *= a) if (x & 1) res *= a;
		return res;
	}
	friend ModInt inverse(ModInt a) {return pow(a, MOD - 2);}
 
	ModInt operator+ () const {return ModInt( v);}
	ModInt operator- () const {return ModInt(-v);}
	ModInt operator++() const {return *this += 1;}
	ModInt operator--() const {return *this -= 1;}
 
	friend ModInt operator+(ModInt a, const ModInt &b) {return a += b;}
	friend ModInt operator-(ModInt a, const ModInt &b) {return a -= b;}
	friend ModInt operator*(ModInt a, const ModInt &b) {return a *= b;}
	friend ModInt operator/(ModInt a, const ModInt &b) {return a /= b;}
 
	friend istream &operator>>(istream &is, ModInt &v) {return is >> v.v;}
	friend ostream &operator<<(ostream &os, const ModInt &v) {return os << v.v;}
};
const int ModA	= 998244353;
const int ModC	= 1e9 + 7;
using MintA	= ModInt<ModA>;
using MintC	= ModInt<ModC>;

// Other constants
const ll INF	= 1e18;
const ll iINF	= 1e9;
const ld EPS	= 1e-9;
const ld iEPS	= 1e-6;

const int maxN	= 2523;

int N, M;
char grid[maxN][maxN];
int up[maxN][maxN], dn[maxN][maxN], minH[maxN];
int boundH = iINF, boundW = iINF, ans = 0;

int main() {
	ios_base::sync_with_stdio(false); cin.tie(NULL);

	cin >> N >> M;
	for (int i = 1; i <= N; i++) {
		for (int j = 1; j <= M; j++) {
			cin >> grid[i][j];
		}
	}

	// Precompute up, dn, and boundH
	for (int j = 1; j <= M; j++) {
		for (int i = 1; i <= N; i++) {
			if (grid[i][j] == '0') {
				up[i][j] = 0;
			} else {
				up[i][j] = up[i-1][j] + 1;
				if ((i == N) || (grid[i+1][j] == '0')) {
					boundH = min(boundH, up[i][j]);
				}
			}
		}

		for (int i = N; i >= 1; i--) {
			if (grid[i][j] == '0') {
				dn[i][j] = 0;
			} else {
				dn[i][j] = dn[i+1][j] + 1;
			}
		}
	}

	// Precompute boundW
	for (int i = 1; i <= N; i++) {
		int span = 0;
		for (int j = 1; j <= M; j++) {
			if (grid[i][j] == '0') {
				span = 0;
			} else {
				span += 1;
				if ((j == M) || (grid[i][j+1] == '0')) {
					boundW = min(boundW, span);
				}
			}
		}
	}

	// Compute minH for each horizontal prefix and suffix
	for (int j = 1; j <= M; j++) {
		minH[j] = boundH;
	}
	for (int i = 1; i <= N; i++) {
		int span = 0, mnUp = iINF, mnDn = iINF;
		for (int j = 1; j <= M; j++) {
			if (grid[i][j] == '0') {
				span = 0, mnUp = iINF, mnDn = iINF;
			} else {
				span += 1;
				mnUp = min(mnUp, up[i][j]);
				mnDn = min(mnDn, dn[i][j]);

				minH[span] = min(minH[span], mnUp + mnDn - 1);
			}
		}
		
		span = 0, mnUp = iINF, mnDn = iINF;
		for (int j = M; j >= 1; j--) {
			if (grid[i][j] == '0') {
				span = 0, mnUp = iINF, mnDn = iINF;
			} else {
				span += 1;
				mnUp = min(mnUp, up[i][j]);
				mnDn = min(mnDn, dn[i][j]);

				minH[span] = min(minH[span], mnUp + mnDn - 1);
			}
		}
	}

	for (int j = 1; j <= boundW; j++) {
		ans = max(ans, minH[j] * j);
	}

	cout << ans << '\n';
}

Subtask #1

100.0 / 100.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	340 KB	Output is correct
2	Correct	1 ms	468 KB	Output is correct
3	Correct	9 ms	26580 KB	Output is correct
4	Correct	9 ms	26496 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	468 KB	Output is correct
9	Correct	0 ms	468 KB	Output is correct
10	Correct	1 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	1 ms	404 KB	Output is correct
14	Correct	1 ms	468 KB	Output is correct
15	Correct	0 ms	468 KB	Output is correct
16	Correct	0 ms	468 KB	Output is correct
17	Correct	1 ms	980 KB	Output is correct
18	Correct	1 ms	980 KB	Output is correct
19	Correct	1 ms	1364 KB	Output is correct
20	Correct	1 ms	1236 KB	Output is correct
21	Correct	1 ms	852 KB	Output is correct
22	Correct	1 ms	1108 KB	Output is correct
23	Correct	1 ms	1364 KB	Output is correct
24	Correct	1 ms	1236 KB	Output is correct
25	Correct	1 ms	1364 KB	Output is correct
26	Correct	1 ms	1364 KB	Output is correct
27	Correct	3 ms	3924 KB	Output is correct
28	Correct	5 ms	4180 KB	Output is correct
29	Correct	5 ms	5332 KB	Output is correct
30	Correct	5 ms	6228 KB	Output is correct
31	Correct	4 ms	4948 KB	Output is correct
32	Correct	4 ms	5716 KB	Output is correct
33	Correct	5 ms	6612 KB	Output is correct
34	Correct	3 ms	4692 KB	Output is correct
35	Correct	5 ms	6556 KB	Output is correct
36	Correct	6 ms	6612 KB	Output is correct
37	Correct	1 ms	468 KB	Output is correct
38	Correct	238 ms	55964 KB	Output is correct
39	Correct	0 ms	468 KB	Output is correct
40	Correct	23 ms	15448 KB	Output is correct
41	Correct	0 ms	468 KB	Output is correct
42	Correct	1 ms	1364 KB	Output is correct
43	Correct	226 ms	55756 KB	Output is correct
44	Correct	6 ms	6612 KB	Output is correct
45	Correct	256 ms	55860 KB	Output is correct
46	Correct	233 ms	55852 KB	Output is correct
47	Correct	232 ms	55768 KB	Output is correct
48	Correct	273 ms	55876 KB	Output is correct
49	Correct	234 ms	55864 KB	Output is correct
50	Correct	234 ms	55900 KB	Output is correct
51	Correct	259 ms	55828 KB	Output is correct
52	Correct	237 ms	55868 KB	Output is correct
53	Correct	240 ms	55756 KB	Output is correct
54	Correct	231 ms	55772 KB	Output is correct
55	Correct	232 ms	55808 KB	Output is correct
56	Correct	240 ms	55992 KB	Output is correct
57	Correct	240 ms	55960 KB	Output is correct
58	Correct	242 ms	55808 KB	Output is correct
59	Correct	223 ms	55864 KB	Output is correct
60	Correct	227 ms	55860 KB	Output is correct
61	Correct	228 ms	55876 KB	Output is correct
62	Correct	234 ms	55780 KB	Output is correct
63	Correct	270 ms	55860 KB	Output is correct
64	Correct	305 ms	55872 KB	Output is correct
65	Correct	234 ms	55860 KB	Output is correct
66	Correct	250 ms	55860 KB	Output is correct
67	Correct	234 ms	55760 KB	Output is correct
68	Correct	236 ms	55864 KB	Output is correct
69	Correct	218 ms	55860 KB	Output is correct
70	Correct	140 ms	44752 KB	Output is correct
71	Correct	222 ms	55840 KB	Output is correct
72	Correct	214 ms	55976 KB	Output is correct
73	Correct	265 ms	55848 KB	Output is correct
74	Correct	229 ms	55860 KB	Output is correct
75	Correct	230 ms	55864 KB	Output is correct
76	Correct	252 ms	55828 KB	Output is correct
77	Correct	230 ms	55860 KB	Output is correct
78	Correct	247 ms	55872 KB	Output is correct
79	Correct	219 ms	55776 KB	Output is correct
80	Correct	219 ms	55860 KB	Output is correct
81	Correct	208 ms	55760 KB	Output is correct
82	Correct	223 ms	55820 KB	Output is correct
83	Correct	225 ms	55956 KB	Output is correct
84	Correct	214 ms	55876 KB	Output is correct
85	Correct	238 ms	55864 KB	Output is correct
86	Correct	239 ms	55860 KB	Output is correct
87	Correct	235 ms	55868 KB	Output is correct
88	Correct	280 ms	55760 KB	Output is correct
89	Correct	230 ms	55864 KB	Output is correct
90	Correct	147 ms	44648 KB	Output is correct
91	Correct	242 ms	55756 KB	Output is correct
92	Correct	231 ms	55752 KB	Output is correct
93	Correct	241 ms	55824 KB	Output is correct
94	Correct	233 ms	55856 KB	Output is correct
95	Correct	312 ms	55864 KB	Output is correct
96	Correct	272 ms	55864 KB	Output is correct
97	Correct	241 ms	55788 KB	Output is correct
98	Correct	230 ms	55852 KB	Output is correct
99	Correct	216 ms	55872 KB	Output is correct
100	Correct	228 ms	55864 KB	Output is correct