HDU 2295 Dance chain can be repeated overlay + two points

Click to open link

Test instructions: gives n points and m centers, in the case of not more than K circle, so that all points are covered, the smallest radius of the circle of how much

Train of thought: Ask the smallest what what then use two quasi-accurate, then what is the second condition, is to use not more than K of the circle can all points covered, covering this part is the naked dance chain can be repeated coverage, behavior M Circle, listed as N points, and then find the minimum line less than or equal to K, then set up, or not

#include <math.h> #include <vector> #include <stdio.h> #include <string.h> #include < stdlib.h> #include <iostream> #include <algorithm>using namespace std;typedef long Long ll;typedef unsigned long long ull;const int inf=0x3f3f3f3f;const ll inf=0x3f3f3f3f3f3f3f3fll;const int Maxn=310;const double eps=1e- 8;int l[maxn*maxn],r[maxn*maxn],u[maxn*maxn],d[maxn*maxn];//node up and down four-way linked list int C[maxn*maxn],h[maxn],cnt[maxn],vis [maxn];//c column h row CNT list number of elements int n,m,id,fans,k;void init (int lll) {for (int i=0;i<=lll;i++) {cnt[i]=0;        U[i]=d[i]=i; L[i+1]=i;    r[i]=i+1;    } r[lll]=0;id=lll+1; memset (h,-1,sizeof (H)); void Link (int r,int c) {cnt[c]++;    C[id]=c;    U[ID]=U[C];D [U[c]]=id; D[id]=c;    U[c]=id;    if (h[r]==-1) H[r]=l[id]=r[id]=id; else{L[id]=l[h[r]];        R[l[h[r]]]=id; R[ID]=H[R];    L[h[r]]=id; } id++;} void Remove (int Size) {for (int j=d[size];j!=size;j=d[j]) l[r[j]]=l[j],r[l[j]]=r[j];} void Resume (int Size) {for (intJ=D[SIZE];J!=SIZE;J=D[J]) L[r[j]]=r[l[j]]=j;}    int h () {int sum=0;    memset (vis,0,sizeof (VIS));        for (int i=r[0];i;i=r[i]) {if (vis[i]) continue;        sum++;        For (int. J=d[i];j!=i;j=d[j]) {for (int k=r[j];k!=j;k=r[k]) vis[c[k]]=1; }} return sum;}    void Dance (int k) {int mm=maxn,pos;    if (K+h () >=fans) return; if (!        R[0]) {if (K<fans) fans=k;    Return    } for (int i=r[0];i;i=r[i]) if (mm>cnt[i]) mm=cnt[i],pos=i;        for (int i=d[pos];i!=pos;i=d[i]) {Remove (i);        for (int j=r[i];j!=i;j=r[j]) Remove (j);        Dance (k+1);        for (int j=r[i];j!=i;j=r[j]) Resume (j);    Resume (i);    }}int a[110][2],b[110][2];d ouble calcdis (int i,int j) {Double ttt= (a[i][0]-b[j][0]) * (a[i][0]-b[j][0]);    Double ppp= (a[i][1]-b[j][1]) * (a[i][1]-b[j][1]);    Double ans=sqrt (TTT+PPP); return ans;}    BOOL Judge (double mid) {init (n); fans=k+1; for (int i=1;i<=n;i++) {for (int j=1;j<=m;j++) {double Ttt=calcdis (i,j);        if (ttt<=mid) Link (j,i);    }} Dance (0);    if (fans<=k) return 1; else return 0;}    int main () {int T;    scanf ("%d", &t);        while (t--) {scanf ("%d%d%d", &n,&m,&k);        for (int i=1;i<=n;i++) scanf ("%d%d", &a[i][0],&a[i][1]);        for (int i=1;i<=m;i++) scanf ("%d%d", &b[i][0],&b[i][1]);        Double le=0,ri=10000.0;            while (ri-le>eps) {double mid= (Le+ri)/2;            if (judge (mid)) Ri=mid;        else Le=mid;    } printf ("%.6lf\n", RI); } return 0;}

HDU 2295 Dance chain can be repeated overlay + two points