Codeforces beta round #99 (Div. 1) C mushroom gnomes-2 (Single Point query)

There are n trees and M mushrooms. Each tree has coordinates a, height h, the probability to the left, and the probability to the right (the probability is represented by 0 ), the mushrooms in the left inverted range [X-h, x) are destroyed, and the mushrooms in the right inverted range (x, x + H] are destroyed. Each mushroom has coordinate B and its magic value Z.

Ask about the magic values and expectations of mushrooms after the tree falls down.

After discretization, the segments are updated, that is, the intervals in the fall range of the tree are all multiplied by the probability of the backward side. The probability of survival of each mushroom is multiplied by its magic value.

#include <iostream>#include <cstdio>#include <cstring>#include <vector>#include <map>#include <algorithm>using namespace std;#define LL(x) (x<<1)#define RR(x) (x<<1|1)#define MID(a,b) (a+((b-a)>>1))const int N=1e5+5;struct OP{double flag;int st,ed,lft;OP(){}OP(int a,int b,double c,int d){st=a;ed=b;flag=c;lft=d;}};struct node{double P;int lft,rht,flag;int mid(){return MID(lft,rht);}void fun(double tmp){P*=tmp;flag=1;}};int B[N],Z[N];vector<OP> op;vector<int> Y;map<int,int> H;struct Segtree{node tree[N*4*4];void PushDown(int ind){if(tree[ind].flag){tree[LL(ind)].fun(tree[ind].P);tree[RR(ind)].fun(tree[ind].P);tree[ind].flag=0;tree[ind].P=1;}}void build(int lft,int rht,int ind){tree[ind].lft=lft;tree[ind].rht=rht;tree[ind].P=1;tree[ind].flag=0;if(lft!=rht){int mid=tree[ind].mid();build(lft,mid,LL(ind));build(mid+1,rht,RR(ind));}}void updata(int st,int ed,int ind,double flag){int lft=tree[ind].lft,rht=tree[ind].rht;if(st<=lft&&rht<=ed) tree[ind].fun(flag);else{PushDown(ind);int mid=tree[ind].mid();if(st<=mid) updata(st,ed,LL(ind),flag);if(ed> mid) updata(st,ed,RR(ind),flag);}}double query(int pos,int ind){if(tree[ind].lft==tree[ind].rht) return tree[ind].P;else{PushDown(ind);int mid=tree[ind].mid();if(pos<=mid) return query(pos,LL(ind));else return query(pos,RR(ind));}}}seg;int main(){int n,m;while(scanf("%d%d",&n,&m)!=EOF){Y.clear(); H.clear(); op.clear();for(int i=0;i<n;i++){int a,b,c,d; scanf("%d%d%d%d",&a,&b,&c,&d);Y.push_back(a-b); Y.push_back(a+b);Y.push_back(a);op.push_back(OP(a-b,a,(100-c)/100.0,1));op.push_back(OP(a,a+b,(100-d)/100.0,0));}for(int i=0;i<m;i++){scanf("%d%d",&B[i],&Z[i]);Y.push_back(B[i]);}sort(Y.begin(),Y.end());Y.erase(unique(Y.begin(),Y.end()),Y.end());for(int i=0;i<(int)Y.size();i++) H[Y[i]]=i;seg.build(0,(int)Y.size(),1);for(int i=0;i<(int)op.size();i++){if(op[i].lft) seg.updata(H[op[i].st],H[op[i].ed]-1,1,op[i].flag);else seg.updata(H[op[i].st]+1,H[op[i].ed],1,op[i].flag);}double res=0;for(int i=0;i<m;i++){res+=Z[i]*seg.query(H[B[i]],1);}printf("%.4lf\n",res);}return 0;}