Submission #740106

#	Time	Username	Problem	Language	Result	Execution time	Memory
740106		vjudge1	Fountain Parks (IOI21_parks)	C++17	Compilation error	0 ms	0 KiB

parks

#include "parks.h"
#include <bits/stdc++.h>
#define f first
#define s second 
#define ent '\n'
//#define int long long

#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#pragma GCC optimize("Ofast,unroll-loops,fast-math,O3")

//typedef long double ld;
typedef long long ll;
using namespace std;
 
struct node{double x,y;};
//double len(node a,node b)
//{return sqrt((a.x-b.x)*(a.x-b.y)+(a.y-b.y)*(a.x-b.y));}

struct seg{
	int l,r,id;
};

const string out[2]={"NO\n","YES\n"};
const ll dx[]={-1,-1,1,1};  
const ll dy[]={-1,1,-1,1};
const ll dxx[]={0,0,2,-2};
const ll dyy[]={2,-2,0,0};
const int md=998244353;
const int mod=1e9+7;
const int mx=8e5+12; 
const int tst=1e5;
const bool T=0;

pair<int,pair<int,int>> p[mx];
map<int,bool> used[mx];
map<int,int> pos[mx];
vector<int> g[mx];
int ma[mx];
int mi[mx];

void dfs(int x,int y){
	used[x][y]=1;
	ma[x]=max(ma[x],y);
	mi[x]=min(mi[x],y);
	for(int k=0;k<4;k++){
		int x1=x+dxx[k];
		int y1=y+dyy[k];
		if(!used[x1].count(y1) && pos[x1].count(y1))dfs(x1,y1);
	}
}

int construct_roads(std::vector<int> x, std::vector<int> y) {
	n=x.size();
	for(int i=1;i<=n;i++){
		p[i]={x[i-1],{y[i-1],i}};
	}
	sort(p+1,p+n+1);
	int mx=0;
	reverse(x.begin(),x.end());
	reverse(y.begin(),y.end());
	x.push_back(0);
	y.push_back(0);
	reverse(x.begin(),x.end());
	reverse(y.begin(),y.end());
	for(int i=1;i<=n;i++){
		mx=max(mx,x[i]);
		pos[x[i]][y[i]]=i-1;
	}
	for(int i=0;i<=mx;i++)mi[i]=1e9;
	dfs(x[1],y[1]);
	for(int i=1;i<=n;i++){
		if(!used[x[i]][y[i]]){
			return 0;
		}
	}
	vector<int> u,v,a,b;
	if(mx<=6){
		for(int i=mi[2];i<ma[2];i+=2){
			u.push_back(pos[2][i]);
			v.push_back(pos[2][i+2]);
			a.push_back(1);
			b.push_back(i-1);
		}
		if(mx==2){
			build(u,v,a,b);
			return 1;
		}
		for(int i=mi[4];i<ma[4];i+=2){
			u.push_back(pos[4][i]);
			v.push_back(pos[4][i+2]);
			a.push_back(3);
			b.push_back(i-1);
		}
		if(ma[2]<ma[4]){
			u.push_back(pos[2][ma[2]]);
			v.push_back(pos[4][ma[2]]);
			a.push_back(1);
			b.push_back(ma[2]+1);
		}
		else{
			u.push_back(pos[2][ma[4]]);
			v.push_back(pos[4][ma[4]]);
			a.push_back(3);
			b.push_back(ma[4]+1);
		}
		if(mx==4){
			build(u,v,a,b);
			return 1;
		}
		for(int i=mi[6];i<ma[6];i+=2){
			u.push_back(pos[6][i]);
			v.push_back(pos[6][i+2]);
			a.push_back(7);
			b.push_back(i-1);
		}
		int x=min(ma[4],ma[6]);
		u.push_back(pos[4][x]);
		v.push_back(pos[6][x]);
		a.push_back(5);
		b.push_back(x+1);
		build(u,v,a,b);
		return 1;
	}
	return 0;
}

Compilation message (stderr)

parks.cpp: In function 'int construct_roads(std::vector<int>, std::vector<int>)':
parks.cpp:53:2: error: 'n' was not declared in this scope
   53 |  n=x.size();
      |  ^