답안 #596186

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
596186 2022-07-14T13:07:44 Z andrei_boaca The Forest of Fangorn (CEOI14_fangorn) C++14
0 / 100
931 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=360;
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);
    assert(conv==0);
    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:216:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  216 |                 for(int j=0;j<mylines.size();j++)
      |                             ~^~~~~~~~~~~~~~~
# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 340 KB Output is correct
2 Runtime error 1 ms 468 KB Execution killed with signal 6
3 Incorrect 1 ms 340 KB Output isn't correct
4 Runtime error 2 ms 596 KB Execution killed with signal 6
5 Correct 1 ms 340 KB Output is correct
6 Correct 3 ms 340 KB Output is correct
7 Incorrect 184 ms 596 KB Output isn't correct
8 Incorrect 133 ms 596 KB Output isn't correct
# 결과 실행 시간 메모리 Grader output
1 Incorrect 54 ms 400 KB Output isn't correct
2 Incorrect 93 ms 468 KB Output isn't correct
3 Incorrect 220 ms 596 KB Output isn't correct
4 Incorrect 262 ms 596 KB Output isn't correct
5 Incorrect 265 ms 596 KB Output isn't correct
6 Incorrect 734 ms 1356 KB Output isn't correct
7 Correct 1 ms 340 KB Output is correct
8 Correct 10 ms 340 KB Output is correct
9 Incorrect 176 ms 596 KB Output isn't correct
10 Incorrect 931 ms 1356 KB Output isn't correct
11 Correct 885 ms 2504 KB Output is correct
12 Incorrect 701 ms 1356 KB Output isn't correct
# 결과 실행 시간 메모리 Grader output
1 Runtime error 2 ms 596 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Runtime error 93 ms 65536 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -