BZOJ 2648/2716(SJY把件-KD_Tree)[Template:KD_Tree]
2648: SJY把件
Time Limit: 20 Sec Memory Limit: 128 MBSubmit: 1180 Solved: 391
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Description
和M<=500000个操作。
对于每一个白色棋子,输出距离这个白色棋子近期的黑色棋子的距离。同一个格子可能有多个棋子。
Input
Output
Sample Input
1 1
2 3
2 1 2
1 3 3
2 4 2
Sample Output
1
2
HINT
kdtree能够过
Source
提示中已有kd-tree了,那么百度一下
考虑平面上一堆点,先找出横坐标中位数的点。取出。对着切一刀,剩下点分为2半
然后对当中一边竖着切,再横着切。。。。
转自:http://www.cnblogs.com/slysky/archive/2011/11/08/2241247.html
#include<cstdio> #include<cstring> #include<cstdlib> #include<algorithm> #include<functional> #include<iostream> #include<cmath> #include<cctype> #include<ctime> using namespace std; #define For(i,n) for(int i=1;i<=n;i++) #define Fork(i,k,n) for(int i=k;i<=n;i++) #define Rep(i,n) for(int i=0;i<n;i++) #define ForD(i,n) for(int i=n;i;i--) #define RepD(i,n) for(int i=n;i>=0;i--) #define Forp(x) for(int p=pre[x];p;p=next[p]) #define Forpiter(x) for(int &p=iter[x];p;p=next[p]) #define Lson (x<<1) #define Rson ((x<<1)+1) #define MEM(a) memset(a,0,sizeof(a)); #define MEMI(a) memset(a,127,sizeof(a)); #define MEMi(a) memset(a,128,sizeof(a)); #define INF (1000000000) #define F (100000007) #define MAXN (500000+10) #define MAXM (500000+10) typedef long long ll; ll mul(ll a,ll b){return (a*b)%F;} ll add(ll a,ll b){return (a+b)%F;} ll sub(ll a,ll b){return (a-b+(a-b)/F*F+F)%F;} void upd(ll &a,ll b){a=(a%F+b%F)%F;} int n,m; int cmp_d=0; class node { public: int x[2]; int l,r,minv[2],maxv[2]; node(){} node(int a,int b){MEM(x) l=r=0; x[0]=a,x[1]=b; Rep(i,2) minv[i]=maxv[i]=x[i];} int& operator[](int i){return x[i]; } }; int dis(node a,node b){ int ans=0; Rep(i,2) ans+=abs(a.x[i]-b.x[i]); return ans; } int dis2(node p,node a) // 点p和方形区域a的欧几里德距离 { int ans=0; Rep(i,2) { if (p.x[i]<a.minv[i]) ans+=a.minv[i]-p.x[i]; else if (p.x[i]>a.maxv[i]) ans+=p.x[i]-a.maxv[i]; } return ans; } int cmp(node a,node b){return a[cmp_d]<b[cmp_d]; } class KD_Tree { public: node a[MAXN*3]; KD_Tree() { } void mem() { } void update(node& o) { if (o.l) { node p=a[o.l]; Rep(i,2) o.minv[i]=min(o.minv[i],p.minv[i]); Rep(i,2) o.maxv[i]=max(o.maxv[i],p.maxv[i]); } if (o.r) { node p=a[o.r]; Rep(i,2) o.minv[i]=min(o.minv[i],p.minv[i]); Rep(i,2) o.maxv[i]=max(o.maxv[i],p.maxv[i]); } } int build(int L,int R,int nowd) { int m=(L+R)>>1; cmp_d=nowd; nth_element(a+L+1,a+m+1,a+R+1,cmp); if (L^m) a[m].l=build(L,m-1,nowd^1); if (R^m) a[m].r=build(m+1,R,nowd^1); update(a[m]); return m; } int root; void _build(int L,int R,int nowd) { root=build(L,R,nowd); } void insert(int o,int k,int nowd) { int p=a[o].x[nowd]; int p2=a[k].x[nowd]; if (p2<=p) { if (a[o].l) insert(a[o].l,k,nowd^1); else a[o].l=k; } else { if (a[o].r) insert(a[o].r,k,nowd^1); else a[o].r=k; } update(a[o]); } void _insert(int k,int nowd) { int p=root; insert(root,k,nowd); } node _p; int _ans; void ask_min_dis(int o) { if (o==0) return; _ans=min(_ans,dis(a[o],_p)); int ans1=a[o].l ?dis2(_p,a[a[o].l]) : INF; // 点p到区域内随意一点的距离的最小值 int ans2=a[o].r ? dis2(_p,a[a[o].r]) : INF; if (ans1<ans2) { if(ans1<_ans) ask_min_dis(a[o].l); if(ans2<_ans) ask_min_dis(a[o].r); } else { if(ans2<_ans) ask_min_dis(a[o].r); if(ans1<_ans) ask_min_dis(a[o].l); } } int _ask(node p) { _p=p;_ans=INF; ask_min_dis(root); return _ans; } }S; int main() { // freopen("bzoj2648.in","r",stdin); // freopen("bzoj2648.out","w",stdout); cin>>n>>m; For(i,n) { int x,y; scanf("%d%d",&x,&y); S.a[i]=node(x,y); } S.a[++n]=node(INF,INF); S._build(1,n,0); For(i,m) { int p,x,y; scanf("%d%d%d",&p,&x,&y); if (p==1) { S.a[++n]=node(x,y); S._insert(n,0); } else { printf("%d\n",S._ask(node(x,y))); } } return 0; }
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