답안 #596963

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
596963 2022-07-15T10:13:06 Z andrei_boaca The Forest of Fangorn (CEOI14_fangorn) C++14
15 / 100
3000 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)
{
    if(!inmat(a))
        return 0;
    double d1=dist(L.a,L.b);
    double d2=dist(L.a,a)+dist(a,L.b);
    return abs(d1-d2)<=EPS;
}
double panta(line L)
{
    double a1=L.b.y-L.a.y;
    double b1=L.a.x-L.b.x;
    double 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);
                    bool found=0;
                    if(comun.x==4&&comun.y==3&&L2.a.x==3&&L2.a.y==3)
                        found=1;
                    line u={G,L1.a};
                    line t={G,L2.a};
                    point Ui=intersect(L2,u);
                    point Ti=intersect(L1,t);
                    if(online(Ui,u)||online(Ti,t))
                        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 'double panta(line)':
fangorn.cpp:72:12: warning: unused variable 'c1' [-Wunused-variable]
   72 |     double c1=-a1*L.a.x-b1*L.a.y;
      |            ^~
fangorn.cpp: In function 'int main()':
fangorn.cpp:127:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<line>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  127 |         for(int i=0;i<gol.size()&&ok;i++)
      |                     ~^~~~~~~~~~~
fangorn.cpp:128:28: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<line>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  128 |             for(int j=i+1;j<gol.size()&&ok;j++)
      |                           ~^~~~~~~~~~~
fangorn.cpp:147:26: warning: variable 'found' set but not used [-Wunused-but-set-variable]
  147 |                     bool found=0;
      |                          ^~~~~
# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 304 KB Output is correct
2 Correct 1 ms 308 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 304 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 1 ms 596 KB Output is correct
8 Incorrect 5 ms 596 KB Output isn't correct
# 결과 실행 시간 메모리 Grader output
1 Incorrect 4 ms 340 KB Output isn't correct
2 Correct 9 ms 412 KB Output is correct
3 Correct 55 ms 596 KB Output is correct
4 Correct 2 ms 596 KB Output is correct
5 Correct 2 ms 596 KB Output is correct
6 Correct 12 ms 1196 KB Output is correct
7 Correct 1 ms 212 KB Output is correct
8 Correct 1 ms 304 KB Output is correct
9 Correct 15 ms 588 KB Output is correct
10 Incorrect 247 ms 2348 KB Output isn't correct
11 Incorrect 29 ms 2420 KB Output isn't correct
12 Correct 141 ms 2376 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 384 KB Output is correct
2 Correct 5 ms 304 KB Output is correct
3 Correct 3 ms 340 KB Output is correct
4 Execution timed out 3054 ms 40536 KB Time limit exceeded
5 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Runtime error 48 ms 65536 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -