Submission #210074

#	Time	Username	Problem	Language	Result	Execution time	Memory
210074		bash	Bomb (IZhO17_bomb)	C++17	100 / 100	357 ms	63776 KiB

bomb

/**
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
*/
#include <cstring>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <vector>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <queue>
#include <cmath>
#include <cstdlib>
#include <ctime>
#include <cassert>
 
#define F first
#define S second
#define endl '\n'
#define deb(x) cout<<#x<<' '<<x<<endl;
#define pb push_back
 using namespace __gnu_pbds;
using namespace std;

typedef tree<
int,
null_type,
less<int>,
rb_tree_tag,
tree_order_statistics_node_update>
ordered_set;
/*
#ifdef IZI_KATKA
#define int __int64_t
#else
#define int __int64
#endif
*/
const long long MOD = 1e9 + 7;

typedef long long ll;

#define pii pair<int,int>
 
long long readInt() {
    bool minus1 = false;
    long long result = 0;
    char ch;
    ch = getchar();
    while (true) {
        if (ch == '-') break;
        if (ch >= '0' && ch <= '9') break;
        ch = getchar();
    }
    if (ch == '-') minus1 = true; else result = ch-'0';
    while (true) {
        ch = getchar();
        if (ch < '0' || ch > '9') break;
        result = result*10 + (ch - '0');
    }
    if (minus1)
        return -result;
    else
        return result;
}

const int MAXN = 2600;
 
int n, m;
char s[MAXN][MAXN];
int ans[MAXN];
int up[MAXN][MAXN];
int dw[MAXN][MAXN];
 
int main() {
	#ifdef IZI_KATKA
	assert(freopen("input", "r", stdin));
    assert(freopen("output", "w", stdout));
    #endif
	scanf("%d%d", &n, &m);
	for (int i = 0; i < n; ++i)
		scanf(" %s", s[i]);
	int mxh = n;
	int mxw = m;
	for (int i = 0; i < n; ++i) {
		int cnt = 0;
		for (int j = 0; j < m; ++j) {
			if (s[i][j] == '1')
				++cnt;
			if (s[i][j] == '1' && (j == m - 1 || s[i][j + 1] == '0')) {
				mxw = min(mxw, cnt);
				cnt = 0;
			}
		}
	}
	for (int i = 0; i < m; ++i) {
		int cnt = 0;
		for (int j = 0; j < n; ++j) {
			if (s[j][i] == '1')
				++cnt, up[j][i] = cnt;
			if (s[j][i] == '1' && (j == n - 1 || s[j + 1][i] == '0')) {
				mxh = min(mxh, cnt);
				cnt = 0;
			}
		}
	}
	for (int i = 0; i < m; ++i) {
		int cnt = 0;
		for (int j = n - 1; j >= 0; --j) {
			if (s[j][i] == '1')
				++cnt, dw[j][i] = cnt;
			else
				cnt = 0;
		}
	}
	for (int i = 0; i <= mxw; ++i)
		ans[i] = mxh;
 
	for (int i = 0; i < n; ++i) {
		int a = MAXN;
		int b = MAXN;
		int cnt = 0;
		for (int j = 0; j < m; ++j) {
			if (s[i][j] == '1') {
				a = min(a, up[i][j]);
				b = min(b, dw[i][j]);
				++cnt;
				ans[cnt] = min(ans[cnt], a + b - 1);
			}
			else {
				a = MAXN;
				b = MAXN;
				cnt = 0;
			}
		}
	}
 
	for (int i = 0; i < n; ++i) {
		int a = MAXN;
		int b = MAXN;
		int cnt = 0;
		for (int j = m - 1; j >= 0; --j) {
			if (s[i][j] == '1') {
				a = min(a, up[i][j]);
				b = min(b, dw[i][j]);
				++cnt;
				ans[cnt] = min(ans[cnt], a + b - 1);
			}
			else {
				a = MAXN;
				b = MAXN;
				cnt = 0;
			}
		}
	}
	int res = ans[1];
	for (int i = 1; i <= mxw; ++i)
		res = max(res, i * ans[i]);
	cout << res << "\n";
 
	return 0;
}

Compilation message (stderr)

bomb.cpp: In function 'int main()':
bomb.cpp:91:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d", &n, &m);
  ~~~~~^~~~~~~~~~~~~~~~
bomb.cpp:93:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf(" %s", s[i]);
   ~~~~~^~~~~~~~~~~~~

• Subtask 1: 100 / 100