Submission #596981

# Submission time Handle Problem Language Result Execution time Memory
596981 2022-07-15T10:58:23 Z andrei_boaca The Forest of Fangorn (CEOI14_fangorn) C++14
50 / 100
1559 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 2 ms 976 KB Output is correct
8 Correct 15 ms 992 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 10 ms 340 KB Output is correct
2 Correct 27 ms 528 KB Output is correct
3 Correct 194 ms 888 KB Output is correct
4 Correct 4 ms 912 KB Output is correct
5 Correct 5 ms 912 KB Output is correct
6 Correct 25 ms 2120 KB Output is correct
7 Correct 1 ms 212 KB Output is correct
8 Correct 2 ms 340 KB Output is correct
9 Correct 40 ms 856 KB Output is correct
10 Correct 721 ms 5400 KB Output is correct
11 Correct 1559 ms 4548 KB Output is correct
12 Correct 511 ms 4548 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 31 ms 468 KB Output is correct
3 Correct 8 ms 488 KB Output is correct
4 Runtime error 60 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 -