Data Structures and Algorithms (English) - 7-10 Saving James Bond - Easy Version（25 分）

#include<bits/stdc++.h>#include<cmath>#define mem(a,b) memset(a,b,sizeof a)#define ssclr(ss) ss.clear(), ss.str("")#define INF 0x3f3f3f3f#define MOD 1000000007usingnamespacestd;
typedeflonglongll;
structnode{
doublex,y;
intvis;
};
nodeori;
vector<node>vnd;
intn;
doubled;
doublefdis(nodea, nodeb)
{
returnsqrt(pow(a.x-b.x,2)+pow(a.y-b.y,2));
}
voiddfs(inti)
{
vnd[i].vis=1;
if(50-abs(vnd[i].x)<=d||50-abs(vnd[i].y)<=d)
    {
puts("Yes");
exit(0);
    }
for(intj=0;j<n;j++)
if(!vnd[j].vis&&fdis(vnd[j],vnd[i])<=d) dfs(j);
}
intmain()
{
nodend;
vector<int>vid;
scanf("%d%lf",&n,&d);
for(inti=0;i<n;i++)
    {
scanf("%lf%lf",&nd.x,&nd.y);
nd.vis=0;
vnd.push_back(nd);
    }
if(7.5+d>=50)
    {
puts("Yes");
return0;
    }
for(inti=0;i<n;i++)
if(fdis(vnd[i],ori)<=d+7.5) vid.push_back(i);
for(inti=0;i<vid.size();i++)
if(!vnd[vid[i]].vis) dfs(vid[i]);
puts("No");
return0;
}