답안 #596178

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
596178 2022-07-14T12:58:07 Z andrei_boaca The Forest of Fangorn (CEOI14_fangorn) C++14
0 / 100
96 ms 65536 KB
#include <bits/stdc++.h>

using namespace std;
const double EPS=1e-9;
int n,c,w,h;
struct point
{
    double x,y;
} G,camps[10005],tree[10005];
struct line
{
    point a,b;
};
vector<line> lines;
bool inmat(point p)
{
    return p.x>=0&&p.x<=w&&p.y>=0&&p.y<=h;
}
point intersect(line A, line B)
{
    double a1=A.b.y-A.a.y;
    double b1=A.a.x-A.b.x;
    double c1=-a1*A.a.x-b1*A.a.y;

    double a2=B.b.y-B.a.y;
    double b2=B.a.x-B.b.x;
    double c2=-a2*B.a.x-b2*B.a.y;

    if(a1==0&&a2==0)
        return {-1,-1};
    if(b1==0&&b2==0)
        return {-1,-1};
    if(b2==0)
    {
        swap(a1,a2);
        swap(b1,b2);
        swap(c1,c2);
    }
    double x=(b1*c2-b2*c1)/(a1*b2-a2*b1);
    double y=(-c2-a2*x)/b2;
    return {x,y};
}
double dist(point a, point b)
{
    double val=(a.x-b.x)*(a.x-b.x)+(a.y-b.y)*(a.y-b.y);
    return sqrt(val);
}
vector<int> mylines,sol,Glines;
bool conv=0;
const double beams=15;
const double PI=3.14159265359;
double aria(point a, point b, point c)
{
    a.x-=c.x;
    a.y-=c.y;
    b.x-=c.x;
    b.y-=c.y;
    return a.x*b.y-a.y*b.x;
}
bool online(point a, line L)
{
    double d1=dist(L.a,L.b);
    double d2=dist(L.a,a)+dist(a,L.b);
    return abs(d1-d2)<=EPS;
}
bool prt=0;
void laser(point p)
{
    mylines.clear();
    conv=1;
    double grade=0,rad=0;
    double ip=10.0;
    vector<bool> f;
    f.resize((int)lines.size());
    vector<point> ups,downs,poli;
    for(int i=0;i<lines.size();i++)
    {
        if(online(p,lines[i]))
            mylines.push_back(i);
    }
    while(grade<=beams)
    {
        double x=ip*cos(rad)+p.x;
        double y=ip*sin(rad)+p.y;
        point q={x,y};
        point up={1e9,1e9},down={-1e9,-1e9};
        int lup=-1,ldown=-1;
        line l={p,q};
        for(int i=0;i<lines.size();i++)
        {
            point a=intersect(l,lines[i]);
            if(inmat(a)&&online(a,lines[i]))
            {
                if(a.y>=p.y+EPS&&EPS<up.y-a.y)
                {
                    up=a;
                    lup=i;
                }
                if(a.y<=p.y-EPS&&a.y-down.y>EPS)
                {
                    down=a;
                    ldown=i;
                }
            }
        }
        if(lup>=0)
        {
            f[lup]=1;
            mylines.push_back(lup);
            ups.push_back(up);
        }
        if(ldown>=0)
        {
            f[ldown]=1;
            mylines.push_back(ldown);
            downs.push_back(down);
        }
        grade++;
        rad+=PI/beams;
    }
    //reverse(downs.begin(),downs.end());
    for(auto i:ups)
        poli.push_back(i);
    for(auto i:downs)
        poli.push_back(i);
    sort(mylines.begin(),mylines.end());
    mylines.erase(unique(mylines.begin(),mylines.end()),mylines.end());
    if(prt)
    {
        /*for(auto i:poli)
            cout<<i.x<<' '<<i.y<<'\n';*
        /*for(auto i:mylines)
        {
            line l=lines[i];
            cout<<l.a.x<<' '<<l.a.y<<' '<<l.b.x<<' '<<l.b.y<<'\n';
        }
        cout<<'\n';*/
    }
    conv=1;
    poli.push_back(poli[0]);
    poli.push_back(poli[1]);
    for(int i=2;i<poli.size();i++)
    {
        point a=poli[i-2];
        point b=poli[i-1];
        point c=poli[i];
        /*if(prt)
            cout<<aria(a,b,c)<<'\n';*/
        double AR=aria(a,b,c);
        if(aria(a,b,c)<=-EPS)
        {
            conv=0;
            //break;
        }
    }
}
int main()
{
    cin>>w>>h;
    cin>>G.x>>G.y;
    lines.push_back({{0,0},{0,h}});
    lines.push_back({{0,0},{w,0}});
    lines.push_back({{w,h},{0,h}});
    lines.push_back({{w,h},{w,0}});
    cin>>c;
    for(int i=1;i<=c;i++)
        cin>>camps[i].x>>camps[i].y;
    cin>>n;
    for(int i=1;i<=n;i++)
        cin>>tree[i].x>>tree[i].y;
    for(int i=1;i<=n;i++)
        for(int j=i+1;j<=n;j++)
        {
            line l={tree[i],tree[j]};
            for(int p=0;p<4;p++)
            {
                point a=intersect(lines[p],l);
                if(inmat(a))
                {
                    double d=dist(tree[i],a)+dist(tree[i],tree[j]);
                    double d2=dist(tree[j],a);
                    if(abs(d-d2)<=EPS)
                        lines.push_back({tree[i],a});
                    else
                        lines.push_back({tree[j],a});
                }
            }
        }
    prt=1;
    laser(G);
    if(conv==0)
        mylines.clear();
    else
    {
        Glines=mylines;
        sort(Glines.begin(),Glines.end());
        Glines.erase(unique(Glines.begin(),Glines.end()),Glines.end());
    }
    for(int i=1;i<=c;i++)
    {
        if(i==2)
            prt=0;
        else
            prt=0;
        laser(camps[i]);
        if(conv)
        {
            if(Glines.empty())
                continue;
            sort(mylines.begin(),mylines.end());
            mylines.erase(unique(mylines.begin(),mylines.end()),mylines.end());
            if(mylines.size()==Glines.size())
            {
                bool ok=1;
                for(int j=0;j<mylines.size();j++)
                    if(mylines[j]!=Glines[j])
                        ok=0;
                if(ok)
                    sol.push_back(i);
            }
        }
        else
        {
            if(Glines.empty())
                sol.push_back(i);
        }
    }
    cout<<sol.size()<<'\n';
    for(int i:sol)
        cout<<i<<' ';
    return 0;
}

Compilation message

fangorn.cpp:132:9: warning: "/*" within comment [-Wcomment]
  132 |         /*for(auto i:mylines)
      |          
fangorn.cpp: In function 'void laser(point)':
fangorn.cpp:76:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<line>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   76 |     for(int i=0;i<lines.size();i++)
      |                 ~^~~~~~~~~~~~~
fangorn.cpp:89:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<line>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   89 |         for(int i=0;i<lines.size();i++)
      |                     ~^~~~~~~~~~~~~
fangorn.cpp:142:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<point>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  142 |     for(int i=2;i<poli.size();i++)
      |                 ~^~~~~~~~~~~~
fangorn.cpp:149:16: warning: unused variable 'AR' [-Wunused-variable]
  149 |         double AR=aria(a,b,c);
      |                ^~
fangorn.cpp: In function 'int main()':
fangorn.cpp:161:31: warning: narrowing conversion of 'h' from 'int' to 'double' [-Wnarrowing]
  161 |     lines.push_back({{0,0},{0,h}});
      |                               ^
fangorn.cpp:162:29: warning: narrowing conversion of 'w' from 'int' to 'double' [-Wnarrowing]
  162 |     lines.push_back({{0,0},{w,0}});
      |                             ^
fangorn.cpp:163:23: warning: narrowing conversion of 'w' from 'int' to 'double' [-Wnarrowing]
  163 |     lines.push_back({{w,h},{0,h}});
      |                       ^
fangorn.cpp:163:25: warning: narrowing conversion of 'h' from 'int' to 'double' [-Wnarrowing]
  163 |     lines.push_back({{w,h},{0,h}});
      |                         ^
fangorn.cpp:163:31: warning: narrowing conversion of 'h' from 'int' to 'double' [-Wnarrowing]
  163 |     lines.push_back({{w,h},{0,h}});
      |                               ^
fangorn.cpp:164:23: warning: narrowing conversion of 'w' from 'int' to 'double' [-Wnarrowing]
  164 |     lines.push_back({{w,h},{w,0}});
      |                       ^
fangorn.cpp:164:25: warning: narrowing conversion of 'h' from 'int' to 'double' [-Wnarrowing]
  164 |     lines.push_back({{w,h},{w,0}});
      |                         ^
fangorn.cpp:164:29: warning: narrowing conversion of 'w' from 'int' to 'double' [-Wnarrowing]
  164 |     lines.push_back({{w,h},{w,0}});
      |                             ^
fangorn.cpp:215:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  215 |                 for(int j=0;j<mylines.size();j++)
      |                             ~^~~~~~~~~~~~~~~
# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 0 ms 308 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Incorrect 1 ms 308 KB Output isn't correct
5 Incorrect 0 ms 212 KB Output isn't correct
6 Incorrect 1 ms 212 KB Output isn't correct
7 Incorrect 9 ms 596 KB Output isn't correct
8 Incorrect 11 ms 596 KB Output isn't correct
# 결과 실행 시간 메모리 Grader output
1 Incorrect 4 ms 340 KB Output isn't correct
2 Incorrect 7 ms 468 KB Output isn't correct
3 Incorrect 12 ms 596 KB Output isn't correct
4 Incorrect 15 ms 596 KB Output isn't correct
5 Incorrect 19 ms 596 KB Output isn't correct
6 Incorrect 37 ms 1484 KB Output isn't correct
7 Correct 1 ms 212 KB Output is correct
8 Incorrect 1 ms 340 KB Output isn't correct
9 Incorrect 8 ms 696 KB Output isn't correct
10 Incorrect 44 ms 1484 KB Output isn't correct
11 Correct 42 ms 2504 KB Output is correct
12 Incorrect 32 ms 1484 KB Output isn't correct
# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 212 KB Output is correct
2 Incorrect 4 ms 340 KB Output isn't correct
3 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Runtime error 96 ms 65536 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -