POJ

题目链接点这里

最近真是很怠情啊，不想动手。。。

偶尔敲一题，，都是敲一个小时，，调试2个小时的状态，，，，心累，，

#include<iostream>#include<cstdio>#include<math.h>#include<algorithm>#include<map>#include<set>#include<bitset>#include<stack>#include<queue>#include<string.h>#include<cstring>#include<vector>#include<time.h>#include<stdlib.h>using namespace std;#define INF 0x3f3f3f3f#define INFLL 0x3f3f3f3f3f3f3f3f#define FIN freopen("input.txt","r",stdin)#define mem(x,y) memset(x,y,sizeof(x))typedef unsigned long long ULL;typedef long long LL;#define fuck(x) cout<<"x"<<endl;#define MX 111111#define lson l,m,rt<<1#define rson m+1,r,rt<<1|1typedef pair<pair<int,int>,int> PIII;typedef pair<int,int> PII;const double eps=1e-5;int n,k;const int M=2222,U=1000;//M为U-(y-x)取到的最大值；struct Point {    int x,y,id;    bool operator <(const Point a)const {        if(x!=a.x)return x<a.x;        return y-x<a.y-a.x;    }} w[MX];struct Edge {    int u,v,dist;    bool operator <(const Edge a)const {        return dist<a.dist;    }    Edge() {}    Edge(int u,int v,int dist):u(u),v(v),dist(dist) {}} E[10*MX];int cnt;struct Tree {    int val,id;} tree[MX];void tree_add(int x,int val,int id) {    while(x<=M) {        if(tree[x].val>val) {            tree[x].val=val;            tree[x].id=id;        }        x+=-x&x;    }}PII tree_query(int x) {    int minn=INF,id=-1;    while(x) {        if(tree[x].val<minn) {            minn=tree[x].val;            id=tree[x].id;        }        x-=-x&x;    }    return PII(minn,id);}void build() {    for(int i=0; i<=M; i++)tree[i].id=-1,tree[i].val=INF;    sort(w,w+n);    for(int i=n-1; i>=0; i--) {        PII u=tree_query(U-(w[i].y-w[i].x));        if(u.second!=-1)            E[cnt++]=Edge(w[i].id,u.second,u.first-(w[i].x+w[i].y));        tree_add(U-(w[i].y-w[i].x),w[i].y+w[i].x,w[i].id);    }}int bin[MX];int Find(int x) {    return x==bin[x]?x:bin[x]=Find(bin[x]);}int main() {    FIN;    while(cin>>n>>k) {        for(int i=0; i<n; i++) {            scanf("%d%d",&w[i].x,&w[i].y);            w[i].id=i;        }        cnt=0;        build();        //以x=y翻转        for(int i=0; i<n; i++)swap(w[i].x,w[i].y);        build();        //以x=0翻转        for(int i=0; i<n; i++)w[i].x=-w[i].x;        build();        //以x=y翻转        for(int i=0; i<n; i++)swap(w[i].x,w[i].y);        build();        //求最小生成树部分        sort(E,E+cnt);//有重边        for(int i=1; i<=n; i++)bin[i]=i;        int t=0,ans=0;        k=n-1-k+1;        for(int i=0; i<cnt; i++) {            int fa=Find(E[i].u),fb=Find(E[i].v);            if(fa!=fb)t++,bin[fa]=fb;            if(t==k) {                ans=E[i].dist;                break;            }        }        cout<<ans<<endl;    }    return 0;}