Submission #1003945

#	Time	Username	Problem	Language	Result	Execution time	Memory
1003945		vjudge1	Paint (COI20_paint)	C++17	0 / 100	96 ms	32048 KiB

paint

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

#define fi first
#define se second
#define pb push_back
#define all(x) x.begin(), x.end()
#define allr(x) x.rbegin(), x.rend()
#define mp make_pair

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef complex<double> cd;

const int MAXN = 5e5+10;
const int MOD = 1e9+7;
const int INF = 0x3f3f3f3f;
const ll LINF = 0x3f3f3f3f3f3f3f3f;
const double PI = acos(-1);

int n, m;
vector<vector<set<pii>>> adj;
vector<vector<pii>> pai;
vector<vector<int>> peso, val, mark;
int d[4]={0, 0, 1, -1};

pii find(pii x){ return (pai[x.fi][x.se]==x ? x : pai[x.fi][x.se]=find(pai[x.fi][x.se])); }
void join(pii a, pii b){
	a=find(a); b=find(b);
	if(a==b) return;
	
	if(peso[a.fi][a.se]>peso[b.fi][b.se]) swap(a, b);
	pai[a.fi][a.se]=b;
	peso[b.fi][b.se]=max(peso[b.fi][b.se], peso[a.fi][a.se]+1);
	
	for(auto u : adj[a.fi][a.se])
		adj[b.fi][b.se].insert(u);
		
	adj[a.fi][a.se].clear();
}

void dfs(pii ver){
	mark[ver.fi][ver.se]=1;
	
	for(int i=0;i<4;i++){
		int dx=ver.fi+d[i], dy=ver.se+d[3-i];
		if(dx>=0 && dx<n && dy>=0 && dy<m && val[ver.fi][ver.se]==val[dx][dy] && !mark[dx][dy]){
			join(ver, {dx, dy});
			dfs({dx, dy});
		}
	}
}

void solve(){
	cin >> n >> m;
	pai.resize(n, vector<pii>(m)); peso.resize(n, vector<int>(m, 0)), val.resize(n, vector<int>(m));
	mark.resize(n, vector<int>(m, 0)); adj.resize(n, vector<set<pii>>(m));
	
	for(int i=0;i<n;i++)
		for(int j=0;j<m;j++)
			pai[i][j]={i, j};
	
	for(int i=0;i<n;i++)
		for(int j=0;j<m;j++)
			cin >> val[i][j];
			
	for(int i=0;i<n;i++)
		for(int j=0;j<m;j++)
			if(!mark[i][j])
				dfs({i, j});
	
	for(int i=0;i<n;i++){
		for(int j=0;j<m;j++){
			for(int k=0;k<4;k++){
				int dx=i+d[k], dy=j+d[k];
				if(dx<0 || dx>=n || dy<0 || dy>=m || find({i, j})==find({dx, dy})) continue;
				
				pii a=find({i, j}), b=find({dx, dy});
				adj[a.fi][a.se].insert(b);
				adj[b.fi][b.se].insert(a);
			}
		}
	}
	
	int q; cin >> q;
	while(q--){
		int x, y, c; cin >> x >> y >> c; x--; y--;
		pii p=find({x, y});
		
		vector<pii> temp;
		for(auto u : adj[p.fi][p.se]){
			temp.pb(find(u));
		}
		
		for(auto u : temp)
			if(val[u.fi][u.se]==val[p.fi][p.se]) join(p, u);
		
		p=find(p);
		val[p.fi][p.se]=c;
	}
	
	for(int i=0;i<n;i++){
		for(int j=0;j<n;j++){
			pii p=find({i, j});
			cout << val[p.fi][p.se] << " \n"[j==n-1];
		}
	}
}

int32_t main(){
	//~ ios_base::sync_with_stdio(false); cin.tie(NULL);
	
	int tt=1;
	//~ cin >> tt;
	while(tt--) solve();
	return 0;
}

• Subtask 1: 0 / 8
• Subtask 2: 0 / 9
• Subtask 3: 0 / 31
• Subtask 4: 0 / 52