Submission #1037454

#	Time	Username	Problem	Language	Result	Execution time	Memory
1037454		aaaaaarroz	Soccer Stadium (IOI23_soccer)	C++17	40.50 / 100	4536 ms	39504 KiB

soccer

#include <bits/stdc++.h>
using namespace std;
bool limites(int N, int i, int j){
	return i>=0&&i<N&&j>=0&&j<N;
}
bool comprobar(int N, vector<vector<int>> F){
	for(int i=0;i<N;i++){
		for(int j=0;j<N;j++){
			if(F[i][j]==1){
				continue;
			}
			priority_queue<tuple<int,int,int>,vector<tuple<int,int,int>>,greater<tuple<int,int,int>>>cola;
			int dx[]={1,0,-1,0};
			int dy[]={0,1,0,-1};
			vector<vector<int>>dist(N,vector<int>(N,INT_MAX));
			dist[i][j]=0;
			cola.push({0,i,j});
			while(!cola.empty()){
				auto[d,x,y]=cola.top();
				cola.pop();
				for(int dir=0;dir<4;dir++){
					int posi=x+dx[dir];
					int posj=y+dy[dir];
					while(true){
						if(!limites(N,posi,posj)||F[posi][posj]==1)break;
						if((d+1)<dist[posi][posj]){
							dist[posi][posj]=d+1;
							cola.push({dist[posi][posj],posi,posj});
						}
						posi+=dx[dir];
						posj+=dy[dir];
					}
				}
			}
			for(int x=0;x<N;x++){
				for(int y=0;y<N;y++){
					if(F[x][y]==0&&(dist[x][y]>=3||dist[x][y]==-1)){
						return false;
					}
				}
			}
		}
	}
	return true;
}
int biggest_stadium(int N, vector<vector<int>> F){
	int si_hay_arbol=0;
	pair<int,int>arbol;
	for(int i=0;i<N;i++){
		for(int j=0;j<N;j++){
			if(F[i][j]==0){
				continue;
			}
			else{
				arbol={i,j};
				si_hay_arbol++;
			}
		}
	}
	if(!si_hay_arbol){
		return N*N;
	}
	else if(si_hay_arbol==1){
		int a=((arbol.first+1)*(arbol.second+1))+min((arbol.first+1),(arbol.second+1));
		int b=(((arbol.first+1)*(N-arbol.second))+min((arbol.first+1),(N-arbol.second)));
		int c=(((N-arbol.first)*(arbol.second+1))+min((N-arbol.first),(arbol.second+1)));
		int d=(((N-arbol.first)*(N-arbol.second))+min((N-arbol.first),(N-arbol.second)));
		int e=((arbol.first+1)*(arbol.second+1));
		int f=(((arbol.first+1)*(N-arbol.second)));
		int g=(((N-arbol.first)*(arbol.second+1)));
		int h=(((N-arbol.first)*(N-arbol.second)));
		int max_rectangle=min(min(a,b),min(c,d));
		max_rectangle=min(max_rectangle,min(min(e,f),min(g,h)));
		return (N*N)-max_rectangle;
	}
	else if(N<=7){
		int n = N;
		vector<vector<int>> a = F, next(n, vector<int>(n)), sum(n, vector<int>(n));
		function<int(int, int, int, int)> summ = [&] (int l, int r, int x, int y) {
			long long ans = sum[y][r];
			if (x - 1 >= 0) ans -= sum[x - 1][r];
			if (l - 1 >= 0) ans -= sum[y][l - 1];
			if (x - 1 >= 0 && l - 1 >= 0) ans += sum[x - 1][l - 1];
			return ans;
		};
		function<int(int, int, int, int)> f = [&] (int l, int r, int x, int y) {
			int ans = 0;
			if (x - 1 >= 0) {
				for (int j = l; j <= r; j ++) {
					if (a[x - 1][j]) continue;
					int z = min(r, next[x - 1][j]);
					ans = max(ans, f(j, z, x - 1, y) + z - j + 1);
					j = z;
				}
			}
			if (y + 1 < n) {
				for (int j = l; j <= r; j ++) {
					if (a[y + 1][j]) continue;
					int z = min(r, next[y + 1][j]);
					int ll = y + 1, rr = n, mid;
					while (ll < rr) {
						mid = (ll + rr) / 2;
						if (summ(j, z, x, mid) == 0) ll = mid + 1;
						else rr = mid;
					}
					ll --;
					ans = max(ans, f(j, z, x, ll) + (z - j + 1) * (ll - y));
					j = z;
				}
			}
			return ans;
		};
		for (int i = 0; i < n; i ++) {
			for (int j = 0; j < n; j ++) {
				sum[i][j] += a[i][j];
				if (j) sum[i][j] += sum[i][j - 1];
			}
		}
		for (int i = 1; i < n; i ++) {
			for (int j = 0; j < n; j ++) sum[i][j] += sum[i - 1][j];
		}
		for (int i = 0; i < n; i ++) {
			if (a[i][n - 1] == 0) next[i][n - 1] = n - 1;
			else next[i][n - 1] = n - 2;
			for (int j = n - 2; j >= 0; j --) {
				if (a[i][j]) next[i][j] = j - 1;
				else next[i][j] = next[i][j + 1];
			}
		}
		int ans = 0;
		for (int i = 0; i < n; i ++) {
			for (int j = 0; j < n; j ++) {
				if (a[i][j]) continue;
				ans = max(ans, f(j, next[i][j], i, i) + next[i][j] - j + 1);
				j = next[i][j];
			}
		}
		return ans;
	}
	else{
		int empty_cells=0;
		for(int i=0;i<N;i++){
			for(int j=0;j<N;j++){
				if(F[i][j]==0){
					empty_cells++;
				}	
			}
		}
		bool si=true;
		for(int i=0;i<N;i++){
			for(int j=0;j<N;j++){
				if(F[i][j]==1){
					continue;
				}
				priority_queue<tuple<int,int,int>,vector<tuple<int,int,int>>,greater<tuple<int,int,int>>>cola;
				int dx[]={1,0,-1,0};
				int dy[]={0,1,0,-1};
				vector<vector<int>>dist(N,vector<int>(N,INT_MAX));
				dist[i][j]=0;
				cola.push({0,i,j});
				while(!cola.empty()){
					auto[d,x,y]=cola.top();
					cola.pop();
					for(int dir=0;dir<4;dir++){
						int posi=x+dx[dir];
						int posj=y+dy[dir];
						while(true){
							if(!limites(N,posi,posj)||F[posi][posj]==1)break;
							if((d+1)<dist[posi][posj]){
								dist[posi][posj]=d+1;
								cola.push({dist[posi][posj],posi,posj});
							}
							posi+=dx[dir];
							posj+=dy[dir];
						}
					}
				}
				for(int x=0;x<N;x++){
					for(int y=0;y<N;y++){
						if(F[x][y]==0&&(dist[x][y]>=3||dist[x][y]==-1)){
							si=false;
						}
					}
				}
				if(!si){
					break;
				}
			}
			if(!si){
				break;
			}
		}
		if(si){
			return empty_cells;
		}
		else{
			return 1;
		}
	}
}

• Subtask 0: 0 / 0
• Subtask 1: 6 / 6
• Subtask 2: 8 / 8
• Subtask 3: 22 / 22
• Subtask 4: 4.5 / 18
• Subtask 5: 0 / 16
• Subtask 6: 0 / 30