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QOJ
ID | 题目 | 提交者 | 结果 | 用时 | 内存 | 语言 | 文件大小 | 提交时间 | 测评时间 |
---|---|---|---|---|---|---|---|---|---|
#121199 | #6124. King Of Zombies | EastKing | WA | 1ms | 3716kb | C++17 | 2.7kb | 2023-07-07 19:15:53 | 2023-07-07 19:15:55 |
Judging History
answer
#include<bits/stdc++.h>
using namespace std;
const int M=1005,inf=1e9;
const double eps=1e-6;
#define fi first
#define se second
int n,D;
int dcmp(double x){
if(fabs(x)<0)return 0;
return x>0?1:-1;
}
struct node{
double x,y;
node operator +(const node&tmp)const{
return (node){x+tmp.x,y+tmp.y};
}
node operator -(const node&tmp)const{
return (node){x-tmp.x,y-tmp.y};
}
node operator /(const double &a)const{
return (node){x/a,y/a};
}
node operator *(const double &a)const{
return (node){x*a,y*a};
}
}A[M],V[M];
double dis[M];
typedef pair<double,int> Pi;
double cross(node a,node b){
return a.x*b.y-a.y*b.x;
}
double length(node a){
return sqrt(1.0*a.x*a.x+1.0*a.y*a.y);
}
double disl(node p,node a,node b){
node v=p-a;
node u=b-a;
return fabs(cross(v,u))/length(u);
}
double dot(node a,node b){
return a.x*b.x+a.y*b.y;
}
double calc(node a,node b){
if(dot(a,b)<0)return -1;
double tm=length(a)/length(b);
return tm;
}
node Intersect_line(node a,node b,node c,node d){//两直线交点
//if(cross(b-a,d-c)==0)return node(inf,inf);//前提 不共线
double s1=cross(d-c,a-c);
double s2=cross(d-c,b-c);
return a+(b-a)*s1/(s1-s2);
}
vector<int>update(int x){
vector<int>Q;
for(int i=1;i<=n;i++){
if(i==x)continue;
node v=V[x]-V[i];
node p=A[i];
node a=A[x];
node b=a+v;
if(dcmp(v.x)==0&&dcmp(v.y)==0){
if(dcmp(length(a-p)-D)<=0){
if(dis[i]>dis[x]){
dis[i]=dis[x];
Q.push_back(i);
}
}
continue;
}
double d=disl(p,a,b);
if(dcmp(d-D)>0)continue;
node nl={-v.y,v.x};
double del=sqrt(D*D-d*d);
node dir=v/length(v)*del;
node pot;
if(cross(p-a,v)==0)pot=p;
else pot=Intersect_line(p,p+nl,a,b);
//printf("x=%d i=%d\n",x,i);
double tl=calc(pot+dir-a,v),tr=calc(pot-dir-a,v);
if(dcmp(tl-tr)>0)swap(tl,tr);
//printf("%lf %lf\n",tl,tr);
if(dcmp(dis[x]-tr)<=0){
double val=max(dis[x],tl);
//printf("%lf\n",val);
if(dcmp(dis[i]-val)>0){
dis[i]=val;
Q.push_back(i);
}
}
}
return Q;
}
void solve(){
priority_queue<Pi,vector<Pi>,greater<Pi>>Q;
Q.push({0,0});
int cnt=0;
while(!Q.empty()){
auto now=Q.top();
Q.pop();
int x=now.se;
if(dcmp(now.fi-dis[x])>0)continue;
vector<int>val=update(x);
cnt++;
// if(n==513&&D==10&&x==14){
// printf("cnt=%d\n",cnt);
// }
for(auto v:val){
Q.push({dis[v],v});
}
}
}
int main(){
scanf("%d %d",&n,&D);
for(int i=1;i<=n;i++)dis[i]=inf;
for(int i=0;i<=n;i++){
int x,y,a,b;
scanf("%d %d",&x,&y);
scanf("%d %d",&a,&b);
A[i]={x,y};
V[i]={a,b};
}
solve();
for(int i=1;i<=n;i++){
if(dis[i]==inf){
printf("-1\n");
}else {
printf("%.15f\n",dis[i]);
}
}
return 0;
}
詳細信息
Test #1:
score: 100
Accepted
time: 0ms
memory: 3716kb
input:
5 3 0 0 3 0 10 10 0 -3 1 1 -1 -1 16 1 -1 0 100 100 100 100 -100 -3 10 0
output:
2.626226552146786 0.000000000000000 3.000000000000000 -1 14.285714285714286
result:
ok 5 numbers
Test #2:
score: -100
Wrong Answer
time: 1ms
memory: 3648kb
input:
4 10 0 0 0 0 10 0 0 0 20 0 0 0 30 0 0 0 41 0 0 0
output:
-1 -1 -1 -1
result:
wrong answer 1st numbers differ - expected: '0.0000000', found: '-1.0000000', error = '1.0000000'