POJ 3241 Object Clustering mo team algorithm

Section n-k big Manhattan Distance, MO team algorithm bare title

Object Clustering Time Limit: 2000MS Memory Limit: 131072K Total Submissions: 1584 Accepted: 366 Description We haveN(N≤10000) objects, and wish to classify them in several groups by judgement of their resemblance. To simply the model with each object have 2 indexesaandb(a,b≤500). The resemblance of objectIand objectJis defined byDij= |AI-AJ| + |Bi-BJ|, and then we sayIIsDijResemble toJ. Now we want to find the minimum value ofX, so, we can classify theNObjects intoK(K< N) groups, and in each group, one object are at the mostXResemble to another object in the same group, i.e, for every objectI, ifIIs isn't the only member of the group and then there exists one objectJ(I≠J) in the same group that satisfiesDij≤X Input The first line contains the integers N and K. The following N lines each contain, integers a and b, which describe a object. Output A single line contains the minimum X. Sample Input 6 21 22 32 23 44 33 1 Sample Output 2 Source POJ monthly--2007.08.05, Li, Haoyuan

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/* ***********************************************author:ckbosscreated time:2014 December 20 Saturday 00:27 00 seconds file Name :P oj3241.cpp************************************************ * * #include <iostream> #include <cstdio># Include <cstring> #include <algorithm> #include <string> #include <cmath> #include <cstdlib > #include <vector> #include <queue> #include <set> #include <map>using namespace Std;const int Maxn=22000;const int inf=0x3f3f3f3f;int n,k;struct edge{int u,v,w;} Edge[maxn<<2];int tot;bool cmp_e (Edge A,edge b) {return A.W&LT;B.W;} struct Point{int x,y,id;} Pt[maxn];bool cmp_p (Point A,point B) {if (a.x!=b.x) return A.x<b.x;return a.y<b.y;} int lowbit (int x) {return x& (-X);} int c[4000],d[4000];void update (int id,int pos,int val) {pos+=1000;for (int i=pos;i;i-=lowbit (i)) {if (c[i]>val) {C[i] =val; D[i]=id;}}} void query (int id,int pos,int val) {pos+=1000;int fr=-1,ret=inf;for (int i=pos;i<4000;i+=lowbit (i)) {if (REt>c[i]) {ret=c[i]; Fr=d[i];}} if (fr!=-1) edge[tot++]= (Edge) {id,fr,ret-val};} void Gao () {memset (c,63,sizeof (C)); sort (pt,pt+n,cmp_p); for (int i=n-1;i>=0;i--) {int Pos=pt[i].y-pt[i].x;int sum= Pt[i].y+pt[i].x;int id=pt[i].id;query (id,pos,sum); update (id,pos,sum);}} int fa[maxn];int Find (int x) {if (x==fa[x]) return X;return fa[x]=find (fa[x]);} BOOL Merge (int a,int b) {a=find (a); B=find (b); if (a==b) return False;fa[a]=b;return true;} int solve () {if (n==k) return 0;tot=0;gao (); for (int i=0;i<n;i++) swap (PT[I].X,PT[I].Y), Gao (); for (int i=0;i<n;i++ ) Pt[i].y=-pt[i].y;gao (), for (int i=0;i<n;i++) swap (PT[I].X,PT[I].Y), Gao (), for (int i=0;i<n;i++) Fa[i]=i;sort ( EDGE,EDGE+TOT,CMP_E); for (int i=0;i<tot;i++) {if (merge (EDGE[I].U,EDGE[I].V) ==true) {n--; if (n==k) return EDGE[I].W ;}} return-1;}    int main () {//freopen ("In.txt", "R", stdin);    Freopen ("OUT.txt", "w", stdout); while (scanf ("%d%d", &n,&k)!=eof) {for (int i=0;i<n;i++) {int x,y;scanf ("%d%d", &x,&y);p t[i].x=x; PT [I].y=y; Pt[i].id=i;}printf ("%d\n", Solve ());} return 0;}

POJ 3241 Object Clustering mo team algorithm