Submission #307278

#	Time	Username	Problem	Language	Result	Execution time	Memory
307278		Hemimor	T-Covering (eJOI19_covering)	C++14	100 / 100	143 ms	18672 KiB

covering

#include <algorithm>
#include <iostream>
#include <iomanip>
#include <numeric>
#include <cassert>
#include <vector>
#include <random>
#include <cmath>
#include <queue>
#include <set>
#include <map>
#define syosu(x) fixed<<setprecision(x)
using namespace std;
typedef long long ll;
typedef unsigned int uint;
typedef unsigned long long ull;
typedef pair<int,int> P;
typedef pair<double,double> pdd;
typedef pair<ll,ll> pll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<double> vd;
typedef vector<vd> vvd;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<string> vs;
typedef vector<P> vp;
typedef vector<vp> vvp;
typedef vector<pll> vpll;
typedef pair<int,P> pip;
typedef vector<pip> vip;
const int inf=1<<30;
const ll INF=1ll<<60;
const double pi=acos(-1);
const double eps=1e-8;
const ll mod=1e9+7;
const int dx[8]={-1,0,1,0,1,1,-1,-1},dy[8]={0,1,0,-1,1,-1,1,-1};

vi vin(int n,int d=0){
	vi a(n);
	for(int i=0;i<n;i++){
		cin>>a[i];
		a[i]-=d;
	}
	return a;
}

vl vlin(int n,int d=0){
	vl a(n);
	for(auto &i:a){
		cin>>i;
		i-=d;
	}
	return a;
}

vvi vvin(int n,int m){
	vvi a(n,vi(m));
	for(int i=0;i<n;i++) for(auto &j:a[i]) cin>>j;
	return a;
}

vvi gin(int n,int m,int d=1){
	vvi g(n);
	for(int i=0;i<m;i++){
		int u,v;
		cin>>u>>v;
		u-=d,v-=d;
		g[u].push_back(v);
		g[v].push_back(u);
	}
	return g;
}

void vout(vi a){
	int n=a.size();
	cout<<n<<" :";
	for(auto i:a) cout<<' '<<i;
	cout<<endl;
}

void vvout(vvi a){
	int n=a.size();
	for(int i=0;i<n;i++) vout(a[i]);
}

bool ingrid(int x,int y,int n,int m){
	return 0<=x&&x<n&&0<=y&&y<m;
}

int n,m,k;
vvi a,b,c;
vi x,y,used;

int main(){
	ios::sync_with_stdio(0);
	cin.tie(0);
	cin>>n>>m;
	a=vvin(n,m);
	b=vvi(n,vi(m,-1));
	c=vvi(n,vi(m));
	cin>>k;
	used=x=y=vi(k);
	for(int i=0;i<k;i++){
		cin>>x[i]>>y[i];
		b[x[i]][y[i]]=i;
		c[x[i]][y[i]]++;
	}
	if(c[0][0]||c[0][m-1]||c[n-1][0]||c[n-1][m-1]){
		cout<<"No"<<endl;
		return 0;
	}
	for(int i=0;i<k;i++){
		int B=0,t=0;
		for(int j=0;j<8;j++){
			int X=x[i]+dx[j],Y=y[i]+dy[j];
			if(!ingrid(X,Y,n,m)) B=1;
			else if(b[X][Y]>=0) t++;
		}
		t+=B;
		if(t>=2){
			cout<<"No"<<endl;
			return 0;
		}
		if(t==0) continue;
		for(int j=0;j<4;j++){
			int X=x[i]+dx[j],Y=y[i]+dy[j];
			if(ingrid(X,Y,n,m)) c[X][Y]=1;
		}
		used[i]=1;
	}
	for(int i=0;i<k;i++) if(!used[i]){
		int t=0;
		for(int j=0;j<4;j++){
			int X=x[i]+dx[j],Y=y[i]+dy[j];
			if(ingrid(X,Y,n,m)&&c[X][Y]) t++;
		}
		if(t==0) continue;
		queue<int> q;
		q.push(i);
		used[i]=1;
		while(!q.empty()){
			int I=q.front();q.pop();
			t=0;
			for(int j=0;j<4;j++){
				int X=x[I]+dx[j],Y=y[I]+dy[j];
				if(ingrid(X,Y,n,m)&&c[X][Y]) t++;
			}
			if(t>=2){
				cout<<"No"<<endl;
				return 0;
			}
			for(int j=0;j<4;j++){
				int X=x[I]+dx[j],Y=y[I]+dy[j];
				if(ingrid(X,Y,n,m)) c[X][Y]=1;
			}
			for(int j=0;j<4;j++){
				int X=x[I]+2*dx[j],Y=y[I]+2*dy[j];
				if(ingrid(X,Y,n,m)&&b[X][Y]>=0&&!used[b[X][Y]]){
					used[b[X][Y]]=1;
					q.push(b[X][Y]);
				}
			}
		}
	}
	for(int i=0;i<k;i++) if(!used[i]){
		queue<int> q;
		q.push(i);
		used[i]=2;
		vi d;
		int M=0;
		while(!q.empty()){
			int I=q.front();q.pop();
			d.push_back(I);
			for(int j=0;j<4;j++){
				int X=x[I]+2*dx[j],Y=y[I]+2*dy[j];
				if(ingrid(X,Y,n,m)&&b[X][Y]>=0){
					if(!used[b[X][Y]]){
						used[b[X][Y]]=2;
						q.push(b[X][Y]);
						M++;
					}
					else if(used[b[X][Y]]==2) M++;
				}
			}
		}
		assert(M%2==0);
		M/=2;
		int N=d.size();
		if(M>N){
			cout<<"No"<<endl;
			return 0;
		}
		for(auto I:d) used[I]=1;
		if(N==M){
			for(auto I:d){
				for(int j=0;j<4;j++){
					int X=x[I]+dx[j],Y=y[I]+dy[j];
					if(ingrid(X,Y,n,m)) c[X][Y]=1;
				}
			}
			continue;
		}
		pip p={inf,{0,0}};
		for(auto I:d){
			for(int j=0;j<4;j++){
				int X=x[I]+dx[j],Y=y[I]+dy[j];
				if(ingrid(X,Y,n,m)) p=min(p,{a[X][Y],{X,Y}});
			}
		}
		for(auto I:d){
			for(int j=0;j<4;j++){
				int X=x[I]+dx[j],Y=y[I]+dy[j];
				if(ingrid(X,Y,n,m)){
					if(p.second==make_pair(X,Y)) continue;
					c[X][Y]=1;
				}
			}
		}
	}
	int res=0;
	for(int i=0;i<n;i++) for(int j=0;j<m;j++) res+=a[i][j]*c[i][j];
	cout<<res<<endl;
}

• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 15 / 15
• Subtask 6: 20 / 20
• Subtask 7: 30 / 30