cf1045g AI Robots (dynamic open point segment tree)

Test instructions

Mars has $n$ a line of robots, the first $i$ robot position is $x_{i}$, the field of vision is $r_{i}$, IQ is $q_{i}$. We think that the position $i$ robot can see is $[x_{i}-r_{i},x_{i}+r_{i}]$. If a pair of robots can see each other, and their IQ $q_{i}$ is less than $k$, they will start chatting. To prevent them from arguing, please calculate how many pairs of bots may be chatting.

Exercises

First film, big Guy, here.

We first sort by the field of view in descending order, such a consideration, if the back can see the front, the front will certainly see the back

So, for each robot, in front of him there are several IQ in $[q-k,q+k]$, position in $[x-r,x+r]$

So take this thing as a rectangular overlay.

And then because the IQ of this dimension is very small, we can open a dynamic open point segment tree for each IQ, and then one by one sweep the past statistical answers can be

1 //Minamoto2#include <iostream>3#include <cstdio>4#include <algorithm>5#include <map>6 #definell Long Long7 using namespacestd;8 #defineGetc () (p1==p2&& (p2= (p1=buf) +fread (Buf,1,1<<21,stdin), P1==P2)? eof:*p1++)9 Charbuf[1<< +],*p1=buf,*p2=buf;TenInlineintRead () { One     #defineNum ch-' 0 ' A     CharChBOOLflag=0;intRes; -      while(!isdigit (ch=getc ())) -(ch=='-') && (flag=true); the      for(Res=num;isdigit (Ch=getc ()); res=res*Ten+num); -(flag) && (res=-res); -     #undefNum -     returnRes; + } - Const intn=1e5+5; + intn,k,m,b[n*3];ll Res; Amap<int,int> rt;intl[n<<5],r[n<<5],sum[n<<5],cnt=0; at voidUpdateintPintLintRintx) { -++SUM[P];if(L==R)return; -     intMid= (l+r) >>1; -     if(x<=mid) update (L[p]=l[p]? l[p]:++cnt,l,mid,x); -     ElseUpdate (R[p]=r[p]? R[p]:++cnt,mid+1, r,x); - } in intQueryintPintLintRintQlintqr) { -     if(ql<=l&&qr>=r| | p==0)returnSum[p]; to     intMid= (l+r) >>1, res=0; +     if(Ql<=mid) res+=query (L[P],L,MID,QL,QR); -     if(Qr>mid) Res+=query (r[p],mid+1, R,QL,QR); the     returnRes; * } $InlinevoidInsintQintx) {Panax Notoginseng     if(Rt.count (q) = =0) rt[q]=++CNT; -Update (RT[Q],1, m,x); the } +Inlineint Get(intQintQlintqr) { A     if(Rt.count (q) = =0)return 0; the     returnQuery (Rt[q],1, M,QL,QR); + } - structnode{ $     intx,r,q; $ node () {} -NodeintXintRintq): X (x), R (R), q (q) {} -InlineBOOL operator< (ConstNode &b)Const the{returnR>B.R;} - }a[n];Wuyi intMain () { the //freopen ("testdata.in", "R", stdin); -N=read (), k=read (); Wu      for(intI=1; i<=n;++i) { -         intX=read (), R=read (), q=read (); Abouta[i]=node (x,r,q); $b[++m]=x,b[++m]=x-r,b[++m]=x+R; -     } -Sort (b +1, B +1+M), M=unique (b +1, B +1+M)-b-1; -Sort (A +1, A +1+n); A      for(intI=1; i<=n;++i) { +         intL=lower_bound (b +1, B +1+M,A[I].X-A[I].R)-b; the         intR=lower_bound (b +1, B +1+M,A[I].X+A[I].R)-b; -         intX=lower_bound (b +1, B +1+m,a[i].x)-b; $          for(intj=a[i].q-k;j<=a[i].q+k;++j) theres+=Get(j,l,r); the ins (a[i].q,x); the     } theprintf"%lld\n", res); -     return 0; in}

cf1045g AI Robots (dynamic open point segment tree)