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QOJ

IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#22768#2365. Flight Collisiondonghanwen1225#WA 24ms6944kbC++1.2kb2022-03-10 16:10:092022-04-30 01:38:46

Judging History

你现在查看的是最新测评结果

  • [2023-08-10 23:21:45]
  • System Update: QOJ starts to keep a history of the judgings of all the submissions.
  • [2022-04-30 01:38:46]
  • 评测
  • 测评结果:WA
  • 用时:24ms
  • 内存:6944kb
  • [2022-03-10 16:10:09]
  • 提交

answer

#include<iostream>
#include<cstdio>
#include<queue>
using namespace std;
typedef long long ll;
int n,bj[100001],pre[100001],suf[100001];
ll x[100001],v[100001];
struct node
{
	int l,r;
	double t;
	node(int ll=0,int rr=0,double tt=0){l=ll;r=rr;t=tt;}
	friend bool operator <(const node &a1,const node &a2){return a1.t>a2.t;}
};
priority_queue<node> q;
void sol()
{
	for(int i=1;i<=n;i++) pre[i]=i-1,suf[i]=i+1;
	for(int i=1;i<n;i++)
	{
		if(v[i]==v[i+1]) continue;
		double curt=(x[i+1]-x[i])*1.0/(v[i]-v[i+1]);
		if(curt<0) continue;
		q.push(node(i,i+1,curt));
	}
	while(!q.empty())
	{
		node now=q.top();q.pop();
		if(bj[now.l]||bj[now.r]) continue;
		bj[now.l]=bj[now.r]=1;
		int l=now.l,r=now.r;
		suf[pre[l]]=suf[r];
		pre[suf[r]]=pre[l];
		if(suf[r]<=n&&pre[l]>=1)
		{
			if(v[pre[l]]==v[suf[r]]) continue;
			double curt=(x[suf[r]]-x[pre[l]])*1.0/(v[pre[l]]-v[suf[r]]);
			if(curt<0) continue;
			q.push(node(pre[l],suf[r],curt));
		}
	}
}
int main()
{
	ios::sync_with_stdio(false);
	cin>>n;
	for(int i=1;i<=n;i++) cin>>x[i]>>v[i];
	sol();
	int ans=0;
	for(int i=1;i<=n;i++)
		ans+=!bj[i];
	cout<<ans<<endl;
	for(int i=1;i<=n;i++)
		if(!bj[i]) cout<<i<<" ";
	return 0;
}

Details

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Test #1:

score: 100
Accepted
time: 3ms
memory: 3668kb

input:

1
-4 13

output:

1
1 

result:

ok 2 lines

Test #2:

score: 0
Accepted
time: 3ms
memory: 3628kb

input:

5
1 1000000000
2 1000000000
3 -1000000000
4 -1000000000
5 -1000000000

output:

1
5 

result:

ok 2 lines

Test #3:

score: 0
Accepted
time: 0ms
memory: 3756kb

input:

3
-1000000000 1
999999999 0
1000000000 0

output:

1
3 

result:

ok 2 lines

Test #4:

score: 0
Accepted
time: 0ms
memory: 3628kb

input:

2
5 4
10 5

output:

2
1 2 

result:

ok 2 lines

Test #5:

score: 0
Accepted
time: 3ms
memory: 5708kb

input:

9
10 10
20 7
30 5
40 0
42 0
50 -1
60 -2
70 -10
80 -12

output:

1
1 

result:

ok 2 lines

Test #6:

score: 0
Accepted
time: 3ms
memory: 5664kb

input:

5
10 0
20 0
30 1
40 0
50 0

output:

3
1 2 5 

result:

ok 2 lines

Test #7:

score: 0
Accepted
time: 24ms
memory: 5940kb

input:

98765
0 -48539
1 -48539
2 -48539
3 -48539
4 -48539
5 -48539
6 -48539
7 -48539
8 -48539
9 -48539
10 -48539
11 -48539
12 -48539
13 -48539
14 -48539
15 -48539
16 -48539
17 -48539
18 -48539
19 -48539
20 -48539
21 -48539
22 -48539
23 -48539
24 -48539
25 -48539
26 -48539
27 -48539
28 -48539
29 -48539
30 -...

output:

98765
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 10...

result:

ok 2 lines

Test #8:

score: -100
Wrong Answer
time: 12ms
memory: 6944kb

input:

99999
-999999396 999999395
-999971669 999999396
-999971668 -999999396
-999961260 999999396
-999961259 -999999396
-999907239 999999396
-999907238 -999999396
-999754561 999999396
-999754560 -999999396
-999662011 999999396
-999662010 -999999396
-999651505 999999396
-999651504 -999999396
-999619141 9999...

output:

1
1 

result:

wrong answer 2nd lines differ - expected: '99999', found: '1 '