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POEfficient Algorithm Required For Range Queries
primarykey
Id
12613368
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AcceptedAnswerId
12721085
AnswerCount
2
ClosedDate
CommentCount
9
CommunityOwnedDate
CreationDate
2012-09-27T02:47:37.610
FavoriteCount
1
LastActivityDate
2012-10-04T05:55:19.550
LastEditDate
2012-10-04T05:54:23.390
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1702009
OwnerUserId
1702009
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PostTypeId
1
Score
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ViewCount
801
LastEditorDisplayName
text
Body
I want to know the best way to implement this (approach). I will bee given set of coordinates (x,y). I will then be queried based on those coordinates like 1.C a b => where a and b are integer indexes in the initial set of coordinates. So I need to output the number of points that are in 1st ,2nd ,3rd and fourth quadrant that are in index range a to b. 2.X a b => where a and b are integer indexes in the initial set of coordinates. So I need to mirror the ath to bth indexed coordinates along x axis. 3.Y a b => where a and b are integer indexes in the initial set of coordinates. So I need to mirror the ath to bth indexed coordinates along y axis. there can be at most 100000 coordinates or points and 500000 such queries on them. I tried a brute force method looping through on every query but it had TLE(Time Limit Exceeded). What should I do in such type of questions? Here is my code <pre><code>#include <iostream> #include <stdio.h> using namespace std; char flipX[4] = { 3, 2, 1, 0 }; char flipY[4] = { 1, 0, 3, 2 }; int main(int argc, char **argv) { int n,x,y; char c[100000]; scanf("%d",&n); //coord *c=new coord[n]; for(int i=0;i<n;i++) { scanf("%d",&x); scanf("%d",&y); if(x<0 && y<0) c[i]=2; else if(x>0 && y>0) c[i]=0; else if(x>0 && y<0) c[i]=3; else c[i]=1; } int q,i,j,a,cnt[4]; char ch; scanf("%d",&q); while(q--) { //cout<<"q:"<<q<<endl; cin>>ch; scanf("%d",&i); scanf("%d",&j); i--;j--; if(ch=='X') { //case 'X': for(a=i;a<=j;a++) c[a]=flipX[c[a]]; // break; } else if(ch=='Y') { //case 'Y': for(a=i;a<=j;a++) c[a]=flipY[c[a]]; // break; } else if(ch=='C') { cnt[0]=cnt[1]=cnt[2]=cnt[3]=0; for(a=i;a<=j;a++) { cnt[c[a]]++; } printf("%d %d %d %d\n",cnt[0],cnt[1],cnt[2],cnt[3]); } } return 0; } </code></pre> Please Help.
Tags
<c++><algorithm>
Title
Efficient Algorithm Required For Range Queries
singulars
PostAcceptedAnswerId
1. PO
 singulars
 PostTypePostTypeId
 PTAnswer
PostParentId
1. This table or related slice is empty.
PostTypePostTypeId
1. PTQuestion
UserLastEditorUserId
1. USFluvid
UserOwnerUserId
1. USFluvid
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1. This table or related slice is empty.
PostLinksRelatedPostIdPostId
1. This table or related slice is empty.
PostsAcceptedAnswerId
1. This table or related slice is empty.
PostsParentIdCreationDate
1. PO
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 PostTypePostTypeId
 PTAnswer
2. PO
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 PostTypePostTypeId
 PTAnswer
VotesPostIdCreationDate
1. VO
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 POEfficient Algorithm Required For Range Queries
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