Submission #1216099


Source Code Expand

#include <cstdio>
#include <cstring>
#include <vector>
#include <queue>
#include <string>
#include <algorithm>
#include <iostream>
#include <string>
#include <map>
#include <set>
#include <functional>
#include <iostream>
#define INF 1000000007LL
using namespace std;
typedef long long ll;
typedef pair<int,int> P;

int n;
P p[20001];
int fi[10001],sc[10001];
bool fs[20001];
int V;
vector<int> G[200001];
vector<int> rG[200001];
vector<int> vs;
bool used[200001];
int cmp[200001];

void add_edge(int from,int to){
	G[from].push_back(to);
	rG[to].push_back(from);
}

void dfs(int v){
	used[v]=true;
	for(int i=0;i<G[v].size();i++){
		if(!used[G[v][i]])dfs(G[v][i]);
	}
	vs.push_back(v);
}

void rdfs(int v,int k){
	used[v]=true;
	cmp[v]=k;
	for(int i=0;i<rG[v].size();i++){
		if(!used[rG[v][i]])rdfs(rG[v][i],k);
	}
}

int scc(){
	memset(used,false,sizeof(used));
	vs.clear();
	for(int v=0;v<V;v++){
		if(!used[v])dfs(v);
	}
	memset(used,false,sizeof(used));
	int k=0;
	for(int i=vs.size()-1;i>=0;i--){
		if(!used[vs[i]])rdfs(vs[i],k++);
	}
	return k;
}
int n_=1;

void update(int a,int b,int v,int k=0,int l=0,int r=n_){
	if(r<=a || b<=l)return;
	if(a<=l && r<=b){
		add_edge(n_*2-1+v,k);
		return;
	}
	update(a,b,v,k*2+1,l,(l+r)/2);
	update(a,b,v,k*2+2,(l+r)/2,r);
}

bool C(ll d){
	n_=1;
	while(n_<n*2)n_*=2;
	V=n_*3;
	for(int i=0;i<V;i++){
		G[i].clear();
		rG[i].clear();
	}
	for(int i=0;i+1<n_;i++){
		add_edge(i,i*2+1);
		add_edge(i,i*2+2);
	}
	for(int i=0;i<n*2;i++){
		if(fs[i]){
			add_edge(n_-1+sc[p[i].second],n_*2-1+i);
			add_edge(n_-1+i,n_*2-1+sc[p[i].second]);
		}
		int l=lower_bound(p,p+2*n,P(p[i].first-d+1,0))-p;
		update(l,i,i);
		int r=lower_bound(p,p+2*n,P(p[i].first+d,0))-p;
		update(i+1,r,i);
	}
	scc();
	for(int i=0;i<n;i++){
		if(cmp[n_-1+i]==cmp[n_*2-1+i])return false;
	}
	return true;
}

int main(void){
	scanf("%d",&n);
	for(int i=0;i<n;i++){
		int a,b;
		scanf("%d%d",&a,&b);
		p[i*2]=P(a,i);
		p[i*2+1]=P(b,i);
	}
	sort(p,p+n*2);
	memset(fi,-1,sizeof(fi));
	for(int i=0;i<n*2;i++){
		if(fi[p[i].second]==-1){
			fi[p[i].second]=i;
			fs[i]=true;
		}else{
			sc[p[i].second]=i;
			fs[i]=false;
		}
	}
	ll l=0,r=INF;
	while(l+1<r){
		ll mid=(l+r)/2LL;
		if(C(mid))l=mid;
		else r=mid;
	}
	printf("%lld\n",l);
	return 0;
}

Submission Info

Submission Time
Task F - Flags
User ryoissy
Language C++14 (GCC 5.4.1)
Score 1200
Code Size 2384 Byte
Status AC
Exec Time 706 ms
Memory 27768 KB

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:105:16: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
                ^
./Main.cpp:108:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d",&a,&b);
                      ^

Judge Result

Set Name Sample All
Score / Max Score 0 / 0 1200 / 1200
Status
AC × 3
AC × 30
Set Name Test Cases
Sample 00_example_01.txt, 00_example_02.txt, 00_example_03.txt
All 00_example_01.txt, 00_example_02.txt, 00_example_03.txt, 01.txt, 02.txt, 03.txt, 04.txt, 05.txt, 06.txt, 07.txt, 08.txt, 09.txt, 10.txt, 11.txt, 12.txt, 13.txt, 14.txt, 15.txt, 16.txt, 17.txt, 18.txt, 19.txt, 20.txt, 21.txt, 22.txt, 23.txt, 24.txt, 25.txt, 26.txt, 27.txt
Case Name Status Exec Time Memory
00_example_01.txt AC 5 ms 9856 KB
00_example_02.txt AC 5 ms 9856 KB
00_example_03.txt AC 5 ms 9856 KB
01.txt AC 18 ms 10368 KB
02.txt AC 10 ms 10112 KB
03.txt AC 6 ms 9984 KB
04.txt AC 6 ms 9984 KB
05.txt AC 6 ms 9984 KB
06.txt AC 500 ms 25852 KB
07.txt AC 505 ms 25852 KB
08.txt AC 523 ms 25852 KB
09.txt AC 18 ms 10368 KB
10.txt AC 10 ms 10112 KB
11.txt AC 6 ms 9984 KB
12.txt AC 6 ms 9984 KB
13.txt AC 6 ms 9984 KB
14.txt AC 496 ms 23544 KB
15.txt AC 507 ms 23548 KB
16.txt AC 509 ms 23544 KB
17.txt AC 19 ms 10368 KB
18.txt AC 10 ms 10112 KB
19.txt AC 532 ms 25464 KB
20.txt AC 534 ms 25336 KB
21.txt AC 602 ms 25080 KB
22.txt AC 613 ms 25080 KB
23.txt AC 706 ms 27768 KB
24.txt AC 585 ms 27384 KB
25.txt AC 562 ms 26616 KB
26.txt AC 543 ms 26360 KB
27.txt AC 5 ms 9856 KB