Submission #334582

#	Time	Username	Problem	Language	Result	Execution time	Memory
334582		amunduzbaev	Bomb (IZhO17_bomb)	C++14	100 / 100	178 ms	75884 KiB

bomb

#include <bits/stdc++.h>
using namespace std;
#define ff first
#define ss second
#define pb push_back
#define mp make_pair
#define ub upper_bound
#define lb lower_bound
#define ll long long  
#define ld long double 
#define pii pair<int, int>
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(),x.rend()
#define prc(n) fixed << setprecision(n)
#define fastios ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define pi acos(-1);
const int inf = 1e9+7;
const int N = 2505;
int a[N][N], mnc, mnr, d[N][N], u[N][N], ans[N];

void solve(){
	mnr = inf, mnc = inf;
	int n, m;
	cin>>n>>m;
	for(int i=1;i<=n;i++){
		for(int j=1;j<=m;j++){
			char c;
			cin>>c;
			a[i][j] = c - '0';
		}
	}
	
	for(int i=1;i<=n;i++){
		for(int j=1;j<=m;j++){
			if(a[i][j])u[i][j] = u[i-1][j] + 1;
		}
	}

	for(int i=n;i>0;i--){
		for(int j=1;j<=m;j++){
			if(a[i][j]){
				d[i][j] = d[i+1][j]+1;
				if(a[i+1][j] == 0) mnc = min(mnc, u[i][j]);
			}
		}
	}
	
	
	for(int i=1;i<=m;i++) ans[i] = mnc;
	
	for(int i=1;i<=n;i++){
		int aa = inf, b = inf, c = 0;
		for(int j=1;j<=m;j++){
			if(a[i][j] == 0){
				if(c!=0) mnc = min(c, mnc);
				aa = b = inf, c = 0;
			}else{
				aa = min(aa, d[i][j]);
				b = min(b, u[i][j]);
				c++;
				ans[c] = min(ans[c], b + aa -1);
			}
		}
		
		aa = inf, b = inf, c = 0;
		for(int j = m; j>0; j--){
			if(a[i][j] == 0){
				if(c!=0) mnr = min(mnr, c);
				aa = b = inf, c = 0;
			}else{
				aa = min(d[i][j], aa);
				b = min(u[i][j], b);
				c++;
				ans[c] = min(ans[c], b + aa -1);
			}
		}
		if(c > 0) mnr = min(mnr, c);
	}
	int mx = 0;
	for(int i=1;i<=mnr;i++){
		mx = max(ans[i] * i, mx);
	}
	cout<<mx<<"\n";
	return;
}

 
int main(){
	fastios
	int t = 1;
	//cin>>t;
	while(t--) solve();
	return 0;
}

• Subtask 1: 100 / 100