Submission #832239

#	Time	Username	Problem	Language	Result	Execution time	Memory
832239		vjudge1	Bomb (IZhO17_bomb)	C++14	26 / 100	1094 ms	56744 KiB

bomb

#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];
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 void solve(int dr,int dc){
	mems(z, 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;
	}
	cout<<dr*dc<<endl;
	exit(0);
}

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;
	}
	solve(mnr, mnc);
	int ar = max(1, mnr-100);
	int ac = max(1, mnc-100);
	rep(i,ar,mnr)rep(j,ac,mnc)v.pb({i*j, i, j});
	v.pop_back();
	sort(all(v));
	reverse(all(v));
	for(auto &i:v)solve(i[1], i[2]), cout<<i[1]<<" "<<i[2]<<endl;
	return 0;
}

• Subtask 1: 26 / 100