답안 #596986

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
596986 2022-07-15T11:03:03 Z andrei_boaca The Forest of Fangorn (CEOI14_fangorn) C++14
50 / 100
1485 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 {-1,-1};
    if(b1==0&&b2==0)
        return {-1,-1};
    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={-1,-1};
                    if(issame(L1.a,L2.a))
                        comun=L1.a;
                    if(issame(L1.a,L2.b))
                        comun=L1.a;
                    if(issame(L1.b,L2.a))
                        comun=L1.b;
                    if(issame(L1.b,L2.b))
                        comun=L1.b;
                    if(!inmat(comun))
                        continue;
                    if(issame(L1.a,comun))
                        swap(L1.a,L1.b);
                    if(issame(L2.a,comun))
                        swap(L2.a,L2.b);
                    line u={G,L1.a};
                    line t={G,L2.a};
                    point Ui=intersect(L2,u);
                    point Ti=intersect(L1,t);
                    bool isu=online(Ui,u);
                    bool ist=online(Ti,t);
                    if(isu!=ist)
                        continue;
                    else
                        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++)
      |                           ~^~~~~~~~~~~
# 결과 실행 시간 메모리 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 0 ms 212 KB Output is correct
6 Correct 1 ms 212 KB Output is correct
7 Correct 2 ms 976 KB Output is correct
8 Correct 16 ms 992 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 10 ms 340 KB Output is correct
2 Correct 27 ms 552 KB Output is correct
3 Correct 181 ms 848 KB Output is correct
4 Correct 4 ms 912 KB Output is correct
5 Correct 4 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 2 ms 468 KB Output is correct
9 Correct 35 ms 848 KB Output is correct
10 Correct 727 ms 5396 KB Output is correct
11 Correct 1485 ms 4548 KB Output is correct
12 Correct 494 ms 4548 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 16 ms 468 KB Output is correct
3 Correct 7 ms 468 KB Output is correct
4 Runtime error 60 ms 65536 KB Execution killed with signal 9
5 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Runtime error 51 ms 65536 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -