Submission #596985

# Submission time Handle Problem Language Result Execution time Memory
596985 2022-07-15T11:00:16 Z andrei_boaca The Forest of Fangorn (CEOI14_fangorn) C++14
50 / 100
1531 ms 65536 KB
#include <bits/stdc++.h>

using namespace std;
typedef long double ld;
const ld EPS=1e-9;
int n,c,w,h;
struct point
{
    ld 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)
{
    ld a1=A.b.y-A.a.y;
    ld b1=A.a.x-A.b.x;
    ld c1=-a1*A.a.x-b1*A.a.y;

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

    if(a1==0&&a2==0)
        return {-1e9,-1e9};
    if(b1==0&&b2==0)
        return {-1e9,-1e9};
    if(b2==0)
    {
        swap(a1,a2);
        swap(b1,b2);
        swap(c1,c2);
    }
    ld x=(b1*c2-b2*c1)/(a1*b2-a2*b1);
    ld y=(-c2-a2*x)/b2;
    return {x,y};
}
ld dist(point a, point b)
{
    ld 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 ld beams=360;
const ld PI=3.14159265359;
ld 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)
{
    if(!inmat(a))
        return 0;
    ld d1=dist(L.a,L.b);
    ld d2=dist(L.a,a)+dist(a,L.b);
    return abs(d1-d2)<=EPS;
}
ld panta(line L)
{
    ld a1=L.b.y-L.a.y;
    ld b1=L.a.x-L.b.x;
    ld c1=-a1*L.a.x-b1*L.a.y;
    if(b1==0)
        return 1e9;
    return (-a1)/b1;
}
bool issame(point a, point b)
{
    return abs(a.x-b.x)<=EPS&&abs(a.y-b.y)<=EPS;
}
vector<line> plin,gol;
int main()
{
    cin>>w>>h;
    cin>>G.x>>G.y;
    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++)
            lines.push_back({tree[i],tree[j]});
    for(int z=1;z<=c;z++)
    {
        plin.clear();
        gol.clear();
        for(auto l:lines)
        {
            line q={G,camps[z]};
            point i=intersect(l,q);
            if(inmat(i)&&online(i,q))
                gol.push_back(l);
            else
                plin.push_back(l);
        }
        bool ok=1;
        for(auto L1:plin)
        {
            for(auto L2:gol)
            {
                line u={G,L2.a};
                line t={G,L2.b};
                point Ui=intersect(u,L1);
                point Ti=intersect(t,L1);
                if(inmat(Ui)&&inmat(Ti))
                    if(online(Ui,u)&&online(Ti,t))
                    {
                        ok=0;
                        break;
                    }
            }
            if(!ok)
                break;
        }
        for(int i=0;i<gol.size()&&ok;i++)
            for(int j=i+1;j<gol.size()&&ok;j++)
                {
                    line L1=gol[i];
                    line L2=gol[j];
                    point comun=intersect(L1,L2);
                    if(comun.x==-1e9&&comun.y==-1e9)
                        continue;
                    vector<int> vals;
                    if(!issame(L1.a,comun))
                    {
                        line u={G,L1.a};
                        point Ui=intersect(u,L2);
                        if(online(Ui,u))
                            vals.push_back(1);
                        else
                            vals.push_back(0);
                    }
                    if(!issame(L1.b,comun))
                    {
                        line u={G,L1.b};
                        point Ui=intersect(u,L2);
                        if(online(Ui,u))
                            vals.push_back(1);
                        else
                            vals.push_back(0);
                    }
                    if(!issame(L2.a,comun))
                    {
                        line u={G,L2.a};
                        point Ui=intersect(u,L1);
                        if(online(Ui,u))
                            vals.push_back(1);
                        else
                            vals.push_back(0);
                    }
                    if(!issame(L2.b,comun))
                    {
                        line u={G,L2.b};
                        point Ui=intersect(u,L1);
                        if(online(Ui,u))
                            vals.push_back(1);
                        else
                            vals.push_back(0);
                    }
                    bool all=1;
                    for(int i:vals)
                        if(i!=vals[0])
                            all=0;
                    if(all)
                        ok=0;
                }
        if(ok)
            sol.push_back(z);
    }
    cout<<sol.size()<<'\n';
    for(int i:sol)
        cout<<i<<' ';
    return 0;
}

Compilation message

fangorn.cpp: In function 'ld panta(line)':
fangorn.cpp:73:8: warning: unused variable 'c1' [-Wunused-variable]
   73 |     ld c1=-a1*L.a.x-b1*L.a.y;
      |        ^~
fangorn.cpp: In function 'int main()':
fangorn.cpp:128:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<line>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  128 |         for(int i=0;i<gol.size()&&ok;i++)
      |                     ~^~~~~~~~~~~
fangorn.cpp:129:28: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<line>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  129 |             for(int j=i+1;j<gol.size()&&ok;j++)
      |                           ~^~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 340 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 3 ms 976 KB Output is correct
8 Correct 14 ms 992 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 11 ms 340 KB Output is correct
2 Correct 31 ms 528 KB Output is correct
3 Correct 194 ms 872 KB Output is correct
4 Correct 4 ms 912 KB Output is correct
5 Correct 7 ms 912 KB Output is correct
6 Correct 26 ms 2120 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 36 ms 848 KB Output is correct
10 Correct 774 ms 5404 KB Output is correct
11 Correct 1531 ms 4548 KB Output is correct
12 Correct 491 ms 4548 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 36 ms 512 KB Output is correct
3 Correct 8 ms 468 KB Output is correct
4 Runtime error 71 ms 65536 KB Execution killed with signal 9
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Runtime error 48 ms 65536 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -