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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#370984#4906. 球球zsq1472583695 2ms3752kbC++173.3kb2024-03-29 20:37:262024-03-29 20:37:26

Judging History

你现在查看的是最新测评结果

  • [2024-03-29 20:37:26]
  • 评测
  • 测评结果:5
  • 用时:2ms
  • 内存:3752kb
  • [2024-03-29 20:37:26]
  • 提交

answer

#include<bits/stdc++.h>
using namespace std;
const int N=2e6+500,inf=2e9;

int n,t[N],x[N];

struct node
{
    int l,r;

    friend bool operator<(node a,node b)
    {
        return a.l<b.l;
    }

    friend bool operator<(node a,int b)
    {
        return a.l<b;
    }

    int dis(const int x,const int d) const
    {
        int ll=l-d,rr=r+d;
        if(ll<=x&&rr>=x)return 0;
        return min(abs(ll-x),abs(rr-x));
    }
};

struct Set
{
    int d;set<node>s;

    void insert(int l,int r)
    {
        l+=d,r-=d;
        auto it=lower_bound(s.begin(),s.end(),l);
        if(it!=s.begin())
        {
            it--;
            if((*it).r>=r)return;
            it++;
        }
        if(it==s.end())
        {
            s.insert((node){l,r});
            return;
        }
        if((*it).l<=l&&(*it).r>=r)return;
        // cout<<"int "<<l<<' '<<r<<'\n';
        // for(auto x:s)cout<<x.l<<' '<<x.r<<'\n';
        // if(it!=s.begin())--it,cout<<"IT "<<(*it).l<<' '<<(*it).r<<'\n',++it;
        // else puts("is begin");
        // puts("");
        auto bg=it;
        while(it!=s.end()&&(*it).r<=r)++it;
        s.erase(bg,it);s.insert((node){l,r});
    }

    void clear()
    {
        s.clear();d=0;
    }

    int dis(int x)
    {
        if(s.empty())return inf;
        auto it=lower_bound(s.begin(),s.end(),x);
        if(it==s.end())return (*--it).dis(x,d);
        if(it==s.begin())return (*it).dis(x,d);
        return min((*it).dis(x,d),(*--it).dis(x,d));
    }

    int find(int l,int r,int&mi,int&mx)
    {
        mi=inf,mx=-inf;
        auto it=lower_bound(s.begin(),s.end(),l);
        if(it!=s.end())mi=max(l,(*it).l-d);if(it!=s.begin())it--,mi=((*it).r+d>=l?l:mi);
        it=lower_bound(s.begin(),s.end(),r);
        if(it!=s.end())mx=((*it).l-d<=r?r:-inf);if(it!=s.begin())it--,mx=max(mx,min(r,(*it).r+d));
        if(mi>r)mi=inf;if(mx<l)mx=-inf;
        return mi!=inf;
    }

    void put()
    {
        for(auto x:s)
        {
            cout<<d<<' '<<x.l-d<<' '<<x.r+d<<'\n';
        }
    }
}S,T;

main()
{
    // freopen("in.txt","r",stdin);
    // freopen("out.txt","w",stdout);
    cin>>n;
    for(int i=1;i<=n;i++)cin>>t[i]>>x[i];
    S.insert(0,0),T.insert(0,0);
    for(int i=1;i<=n;i++)
    {
        if(S.s.empty()&&T.s.empty())
        {
            puts("NO");
            return 0;
        }
        int u=x[i-1],v=x[i],dt=t[i]-t[i-1];
        int d1=S.dis(v),d2=T.dis(v),d3=min(d1,T.s.empty()?inf:abs(u-v)),mi,mx;S.find(v-dt,v+dt,mi,mx);
        // cout<<"solve "<<d1<<' '<<d2<<' '<<d3<<' '<<mi<<' '<<mx<<' '<<v-dt<<' '<<v+dt<<'\n';
        if(!T.s.empty()&&u>=v-dt&&u<=v+dt)mi=min(mi,u),mx=max(mx,u);
        if(u==v)S.d+=dt;else S.clear();if(abs(u-v)>dt)T.clear();
        if(d2==0)S.insert(u-dt,u+dt);if(d1<=dt)T.insert(u,u);
        if(d3<=dt)S.insert(v-dt+d3,v+dt-d3);
        if(mi!=inf)
        {
            int w=(dt-abs(v-mi))/2;
            T.insert(min(mi,v)-w,max(mi,v)+w);
        }
        if(mx!=-inf)
        {
            int w=(dt-abs(v-mx))/2;
            T.insert(min(mx,v)-w,max(mx,v)+w);
        }
        // cout<<i<<'\n';
        // cout<<"S:\n";
        // S.put();
        // cout<<"T:\n";
        // T.put();
    }
    if(!S.s.empty()||!T.s.empty())puts("YES");
    else puts("NO");
}

Details

Tip: Click on the bar to expand more detailed information

Subtask #1:

score: 5
Accepted

Test #1:

score: 5
Accepted
time: 0ms
memory: 3496kb

input:

5
2 1
3 2
9 6
10 5
13 -1

output:

NO

result:

ok single line: 'NO'

Test #2:

score: 0
Accepted
time: 1ms
memory: 3700kb

input:

5
1 1
3 2
4 -1
6 4
10 -1

output:

NO

result:

ok single line: 'NO'

Test #3:

score: 0
Accepted
time: 1ms
memory: 3608kb

input:

4
16 13
18 4
20 3
21 5

output:

NO

result:

ok single line: 'NO'

Test #4:

score: 0
Accepted
time: 0ms
memory: 3524kb

input:

5
2 1
3 2
8 6
10 5
13 0

output:

YES

result:

ok single line: 'YES'

Test #5:

score: 0
Accepted
time: 1ms
memory: 3712kb

input:

5
2 1
3 2
9 6
10 5
13 0

output:

YES

result:

ok single line: 'YES'

Test #6:

score: 0
Accepted
time: 0ms
memory: 3672kb

input:

5
1 1
3 2
4 0
6 4
10 -1

output:

YES

result:

ok single line: 'YES'

Test #7:

score: 0
Accepted
time: 0ms
memory: 3716kb

input:

3
1 0
5 5
6 2

output:

YES

result:

ok single line: 'YES'

Test #8:

score: 0
Accepted
time: 0ms
memory: 3548kb

input:

5
2 1
6 0
7 -1
8 2
9 -2

output:

YES

result:

ok single line: 'YES'

Test #9:

score: 0
Accepted
time: 0ms
memory: 3668kb

input:

5
30 10
40 -10
51 9
52 8
53 20

output:

YES

result:

ok single line: 'YES'

Test #10:

score: 0
Accepted
time: 0ms
memory: 3612kb

input:

3
2 2
5 5
6 1

output:

YES

result:

ok single line: 'YES'

Subtask #2:

score: 0
Wrong Answer

Dependency #1:

100%
Accepted

Test #11:

score: 0
Wrong Answer
time: 1ms
memory: 3700kb

input:

100
51823 -51823
80072 -23574
152202 48556
263343 -14629
356859 -38607
441850 -193136
442857 -192129
471412 -108145
504392 -187704
582081 -265393
680615 -220684
775219 -261463
781624 -267868
801370 -287614
899570 -166859
982377 -272221
1048767 -338611
1094930 -189414
1170308 -460152
1222829 -512673
...

output:

NO

result:

wrong answer 1st lines differ - expected: 'YES', found: 'NO'

Subtask #3:

score: 0
Skipped

Dependency #2:

0%

Subtask #4:

score: 0
Wrong Answer

Test #91:

score: 0
Wrong Answer
time: 2ms
memory: 3752kb

input:

5000
6 6
80 80
170 48
240 106
243 179
329 176
412 93
485 176
552 249
555 316
613 371
650 313
733 251
735 253
736 334
815 254
893 333
943 255
965 227
1022 284
1116 205
1174 320
1230 376
1318 378
1336 288
1430 212
1494 276
1562 344
1597 309
1638 350
1716 272
1793 349
1809 365
1908 306
1951 464
2037 42...

output:

NO

result:

wrong answer 1st lines differ - expected: 'YES', found: 'NO'

Subtask #5:

score: 0
Skipped

Dependency #3:

0%

Subtask #6:

score: 0
Skipped

Dependency #5:

0%

Subtask #7:

score: 0
Skipped

Dependency #4:

0%

Subtask #8:

score: 0
Skipped

Dependency #7:

0%