contesthunter#46-A(分块）

http://begin.lydsy.com/JudgeOnline/upload/4840.pdf

#include<cstdio>
#include<cstring>
#include<algorithm>
#include<cmath>
using namespace std;

typedef long long ll;
const double eps=1e-6;

struct my{
       ll m,p,x,y;
       double dis,r;
};

const int maxn=250000+10;

my a[maxn];
bool vis[maxn];
ll maxx[maxn];
ll L[maxn],R[maxn],que[maxn],to[maxn];

bool cmp1(const my &x,const my &y){
     return x.m<y.m;
}

bool cmp2(const my &x,const my &y){
     return x.dis<y.dis;
}

int main(){
    ll x0,y0,p,n;
    double r;
    double x,y;
    scanf("%lld%lld%lld%lf%lld",&x0,&y0,&p,&r,&n);
    for (int i=1;i<=n;i++){
        scanf("%lf%lf%lld%lld%lf",&x,&y,&a[i].m,&a[i].p,&a[i].r);
        a[i].dis=sqrt((x-x0)*(x-x0)+(y-y0)*(y-y0));
    }
    a[0].x=x0,a[0].y=y0,a[0].p=p,a[0].r=r;
    int tot=sqrt(1.0*n+0.1);
    sort(a+1,a+1+n,cmp1);
    for (int i=1;i<=tot;i++){
        L[i]=R[i-1]+1;
        to[i]=L[i];
        R[i]= i==tot?n:L[i]+tot;
        maxx[i]=a[R[i]].m;
    }
    for (int i=1;i<=tot;i++) sort(a+L[i],a+R[i]+1,cmp2);
    que[0]=0;
    int ll=0;
    int rr=0;
    int i=0;
    int pp=0;
    int ans=0;
    while(ll<=rr){
        pp=que[ll++];
        for (i=1;i<=tot&&a[pp].p>=maxx[i];i++){
            for (int j=to[i];j<=R[i]&&a[pp].r+eps>=a[j].dis;j++){
                    if(!vis[j]){
                to[i]++;
                que[++rr]=j;
                ans++;
                vis[j]=true;
                }
            }
        }
        if(i<=tot){//记得写i<=tot。。。。。
        for (int k=L[i];k<=R[i];k++){
                if(a[pp].p>=a[k].m&&a[pp].r+eps>=a[k].dis)
                 {
                     if(!vis[k]){
                     que[++rr]=k;ans++;
                     vis[k]=true;
                     }
                }
        }
    }
    }
   printf("%d",ans);
return 0;
}