Submission #1865599
Source Code Expand
#include <cstdio>
#include <cstring>
#include <stack>
#include <algorithm>
#define MAXN 1000010
using namespace std;
struct edge{
int to,next;
edge(int _to=0,int _next=0):to(_to),next(_next){}
}e[10000000];
int n,sizew,nump,numw;
int g[MAXN],nume;
pair<int,int> a[MAXN];
int dfn[MAXN],low[MAXN];
int last[MAXN];
int p[MAXN][2];
stack<int> S;
bool instack[MAXN];
int c[MAXN],numc;
void addEdge(int u,int v){
e[nume]=edge(v,g[u]);
g[u]=nume++;
}
void build(int x,int cl,int cr,int l,int r,int src){
if(l<=cl && cr<=r){
addEdge(p[sizew+src-1][1],p[x][0]);
addEdge(p[x][1],p[sizew+src-1][0]);
return;
}
int mid=(cl+cr)>>1;
if(l<=mid) build(x<<1,cl,mid,l,r,src);
if(r>mid) build(x<<1|1,mid+1,cr,l,r,src);
}
void tarjan(int x){
S.push(x);
instack[x]=1;
dfn[x]=low[x]=++numw;
for(int i=g[x];~i;i=e[i].next)
if(!dfn[e[i].to]){
tarjan(e[i].to);
if(low[e[i].to]<low[x]) low[x]=low[e[i].to];
}else if(instack[e[i].to]){
if(dfn[e[i].to]<low[x]) low[x]=dfn[e[i].to];
}
if(dfn[x]==low[x]){
++numc;
while(S.top()!=x){
instack[S.top()]=0;
c[S.top()]=numc;
S.pop();
}
instack[S.top()]=0;
c[S.top()]=numc;
S.pop();
}
}
bool check(int lim){
memset(g,-1,sizeof g);
nump=nume=0;
for(sizew=1;sizew<n;sizew<<=1);
for(int i=1;i<=2*sizew-1;i++) p[i][0]=++nump;
for(int i=1;i<=2*sizew-1;i++) p[i][1]=++nump;
for(int i=sizew-1;i;i--){
addEdge(p[i<<1][1],p[i][1]);
addEdge(p[i<<1|1][1],p[i][1]);
addEdge(p[i][0],p[i<<1][0]);
addEdge(p[i][0],p[i<<1|1][0]);
}
memset(last,0,sizeof last);
for(int i=1;i<=n;i++)
if(last[a[i].second]){
int j=last[a[i].second];
addEdge(p[sizew+i-1][0],p[sizew+j-1][1]);
addEdge(p[sizew+j-1][0],p[sizew+i-1][1]);
addEdge(p[sizew+i-1][1],p[sizew+j-1][0]);
addEdge(p[sizew+j-1][1],p[sizew+i-1][0]);
}else last[a[i].second]=i;
for(int i=n-1;i;i--)
if(a[i+1].first-a[i].first<lim){
int l=i+1,r=n;
while(l<r){
int mid=(l+r+1)>>1;
if(a[mid].first-a[i].first<lim) l=mid;
else r=mid-1;
}
build(1,1,sizew,i+1,l,i);
}
memset(dfn,0,sizeof dfn);
numc=numw=0;
for(int i=1;i<=nump;i++)
if(!dfn[i]) tarjan(i);
for(int i=1;i<=n;i++)
if(c[p[sizew+i-1][0]]==c[p[sizew+i-1][1]]) return 0;
return 1;
}
int main(){
#ifdef DEBUG
freopen("F.in","r",stdin);
#endif
scanf("%d",&n);
for(int i=1;i<=n;i++){
int t1,t2;
scanf("%d%d",&t1,&t2);
a[i*2-1]=make_pair(t1,i);
a[i*2]=make_pair(t2,i);
}
n*=2;
sort(a+1,a+n+1);
int l=0,r=a[n].first-a[1].first;
while(l<r){
int mid=(l+r+1)>>1;
if(check(mid)) l=mid;
else r=mid-1;
}
printf("%d\n",l);
return 0;
}
Submission Info
Submission Time
2017-12-11 20:40:59+0900
Task
F - Flags
User
ez_zjt
Language
C++14 (GCC 5.4.1)
Score
1200
Code Size
2708 Byte
Status
AC
Exec Time
447 ms
Memory
102912 KB
Compile Error
./Main.cpp: In function ‘int main()’:
./Main.cpp:107:16: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
scanf("%d",&n);
^
./Main.cpp:110:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
scanf("%d%d",&t1,&t2);
^
Judge Result
Set Name
Sample
All
Score / Max Score
0 / 0
1200 / 1200
Status
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
30 ms
98176 KB
00_example_02.txt
AC
25 ms
83840 KB
00_example_03.txt
AC
36 ms
98176 KB
01.txt
AC
51 ms
98176 KB
02.txt
AC
47 ms
98176 KB
03.txt
AC
45 ms
98176 KB
04.txt
AC
46 ms
98176 KB
05.txt
AC
46 ms
98176 KB
06.txt
AC
309 ms
102784 KB
07.txt
AC
309 ms
102784 KB
08.txt
AC
318 ms
102784 KB
09.txt
AC
50 ms
98176 KB
10.txt
AC
47 ms
98176 KB
11.txt
AC
45 ms
98176 KB
12.txt
AC
46 ms
98176 KB
13.txt
AC
46 ms
98176 KB
14.txt
AC
289 ms
102784 KB
15.txt
AC
287 ms
102784 KB
16.txt
AC
287 ms
102784 KB
17.txt
AC
52 ms
98176 KB
18.txt
AC
48 ms
98176 KB
19.txt
AC
338 ms
102784 KB
20.txt
AC
336 ms
102784 KB
21.txt
AC
437 ms
102912 KB
22.txt
AC
443 ms
102912 KB
23.txt
AC
447 ms
102912 KB
24.txt
AC
343 ms
102656 KB
25.txt
AC
363 ms
102784 KB
26.txt
AC
349 ms
102912 KB
27.txt
AC
45 ms
98176 KB