Submission #464468

#	Time	Username	Problem	Language	Result	Execution time	Memory
464468		amunduzbaev	T-Covering (eJOI19_covering)	C++14	100 / 100	282 ms	43892 KiB

covering

#include "bits/stdc++.h"
using namespace std;

#define arr array<int, 2>

void solve(){
	int n, m; cin>>n>>m;
	vector<vector<int>> a(n, vector<int>(m));
	vector<vector<int>> used(n, vector<int>(m));
	vector<vector<int>> is(n, vector<int>(m));
	for(int i=0;i<n;i++){
		for(int j=0;j<m;j++){
			cin>>a[i][j];
		}
	}
	
	int k; cin>>k;
	vector<array<int, 2>> cc(k);
	for(int i=0;i<k;i++){
		cin>>cc[i][0]>>cc[i][1];
	}
	
	for(int i=0;i<k;i++){
		is[cc[i][0]][cc[i][1]] = 1;
	}
	
	int ch[4][2] = {{0, 1}, {0, -1}, {1, 0}, {-1, 0}};
	int ch2[4][2] = {{1, 1}, {1, -1}, {-1, 1}, {-1, -1}};
	for(int i=0;i<k;i++){
		is[cc[i][0]][cc[i][1]] = 1;
	}
	int res = 0;
	auto check = [&](int i, int j) -> bool{
		return (~i && i < n && ~j && j < m);
	}; 
	vector<arr> nw;
	set<arr> ss;
	for(int t=0;t<k;t++){
		int i = cc[t][0], j = cc[t][1], cnt = 0;
		int sum = a[i][j];
		vector<array<int, 3>> aa;
		for(int t=0;t<4;t++){
			int x = i + ch[t][0], y = j + ch[t][1];
			if(!check(x, y)) cnt++;
			else if(is[x][y]) cnt++;
			else sum += a[x][y], aa.push_back({x, y, a[x][y]});
		}
		
		int cnt2 = 0;
		for(int t=0;t<4;t++){
			int x = i + ch2[t][0], y = j + ch2[t][1];
			if(!check(x, y)) continue;
			else if(is[x][y]) cnt2++;
		}
		
		if(cnt2 > 1 || cnt > 1 || (cnt && cnt2)){
			cout<<"No\n";
			return;
		} if(cnt){
			res = res + sum;
			used[i][j] = 1;
			for(auto x : aa) used[x[0]][x[1]] = 1;
		} else if(cnt2){
			res += a[cc[t][0]][cc[t][1]];
			for(auto x : aa){
				if(ss.count({x[0], x[1]})) continue;
				res += x[2];
				ss.insert({x[0], x[1]});
				used[x[0]][x[1]] = 1;
			} used[i][j] = 1;
		} else nw.push_back(cc[t]);
	}
	
	int ch3[4][2] = {{0, -2}, {0, 2}, {2, 0}, {-2, 0}};
	k = (int)nw.size();
	
	vector<vector<vector<arr>>> edges(n, vector<vector<arr>>(m));
	for(int t=0;t<k;t++){
		int i = nw[t][0], j = nw[t][1];
		for(int t=0;t<4;t++){
			int x = i + ch3[t][0], y = j + ch3[t][1];
			if(!check(x, y)) continue;
			
			if(is[x][y] && !used[x][y]) edges[i][j].push_back({x, y});
		}
	}
	
	int cntv, sum, mn, cnt;
	function<void(int, int)> dfs = [&](int i, int j) -> void{
		used[i][j] = 1; sum += a[i][j];
		for(int t=0;t<4;t++){
			int x = i + ch[t][0], y = j + ch[t][1];
			if(!check(x, y) || used[x][y]) continue;
			used[x][y] = 1; sum += a[x][y];
			mn = min(mn, a[x][y]), cnt++;
		}
		
		cntv++;
		for(auto x : edges[i][j]){
			if(used[x[0]][x[1]]) continue;
			dfs(x[0], x[1]);
		}
	};
	
	for(int i=0;i<n;i++){
		for(int j=0;j<m;j++){
			if(used[i][j] || !is[i][j]) continue;
			cnt = 0, cntv = 0, sum = 0, mn = 1e9;
			dfs(i, j); 
			if(cnt < cntv * 3){
				cout<<"No\n";
				return;
			}
			
			res += sum;
			if(cnt > cntv * 3) res -= mn;
		}
	}
	
	cout<<res<<"\n";
}

signed main(){
	ios_base::sync_with_stdio(0); cin.tie(0);
	int t = 1;
	//~ cin>>t;
	while(t--) solve();
}

• 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