Submission #464370

#	Time	Username	Problem	Language	Result	Execution time	Memory
464370		amunduzbaev	T-Covering (eJOI19_covering)	C++14	0 / 100	1096 ms	392 KiB

covering

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

//~ int ch[4][2] = {{0, 1}, {0, -1}, {1, 0}, {-1, 0}};

int ch[4][3][2] = {
	{
		{0, 1}, 
		{0, -1}, 
		{1, 0}
	},
	{
		{0, 1}, 
		{0, -1}, 
		{-1, 0}
	},
	{
		{0, 1}, 
		{-1, 0}, 
		{1, 0}
	},
	{
		{0, -1}, 
		{-1, 0}, 
		{1, 0}
	}
};

void solve(){
	int n, m; cin>>n>>m;
	vector<vector<int>> a(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];
	}
	
	if(k <= 10){
		auto check = [&](int i, int j) -> bool{
			return (~i && i < n && ~j && j < m);
		}; 
	 
		int pw = 1, res = -1;
		for(int i=1;i<k;i++) pw *= 4;
		
		for(int mask=0;mask<pw;mask++){
			int tmp = mask;
			vector<int> bit(k);
			for(int i=0;i<k;i++){
				bit[i] = tmp % 4;
				tmp /= 4;
			}
			
			map<array<int, 2>, bool> mm;
			bool ok = 1;
			int sum = 0;
			for(int i=0;i<k;i++){
				int t = bit[i];
				sum += a[cc[i][0]][cc[i][1]];
				for(int j=0;j<3;j++){
					int x = cc[i][0] + ch[t][j][0], y = cc[i][1] + ch[t][j][1];
					if(!check(x, y)) ok = 0;
					else sum += a[x][y];
					if(mm.count({x, y})) ok = 0;
					mm[{x, y}];
				} mm[{cc[i][0], cc[i][1]}];
			}
			
			if(ok) res = max(res, sum);
		}
		if(res > -1) cout<<res<<"\n";
		else cout<<"No\n";
	} else {
		int ch[4][2] = {{0, 1}, {0, -1}, {1, 0}, {-1, 0}};
		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);
		}; 
	 
		for(int t=0;t<k;t++){
			int i = cc[t][0], j = cc[t][1], cnt = 0;
			int sum = a[i][j], mn = 1e3;
			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], mn = min(mn, a[x][y]);
			} if(cnt > 1) {
				cout<<"No\n";
				return;
			} if(cnt == 1){
				res = res + sum;
			} else {
				res = res + sum - 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: 0 / 5
• Subtask 2: 0 / 10
• Subtask 3: 0 / 10
• Subtask 4: 0 / 10
• Subtask 5: 0 / 15
• Subtask 6: 0 / 20
• Subtask 7: 0 / 30