Small K in the Static Interval... divide tree bare question
Kth number
Time Limit: 15000/5000 MS (Java/others) memory limit: 32768/32768 K (Java/Others)
Total submission (s): 5341 accepted submission (s): 1733
Problem descriptiongive you a sequence and ask you the kth big number of a inteval.
Inputthe first line is the number of the test cases.
For each test case, the first line contain two integer N and M (n, m <= 100000), indicates the number of integers in the sequence and the number of the quaere.
The second line contains N integers, describe the sequence.
Each of following M lines contains three integers S, T, K.
[S, T] indicates the interval and K indicates the kth big number in interval [S, T]
Outputfor each test case, output M lines. Each line contains the kth big number.
Sample Input
1 10 1 1 4 2 3 5 6 7 8 9 0 1 3 2
Sample output
2
Sourcehdu boys' open session-from whu)
#include <iostream>#include <cstdio>#include <cstring>#include <algorithm>using namespace std;const int maxn=100100;int tree[20][maxn];int sorted[maxn];int toleft[20][maxn];void build(int l,int r,int dep){ if(l==r) return ; int mid=(l+r)/2; int same=mid-l+1; for(int i=l;i<=r;i++) if(tree[dep][i]<sorted[mid]) same--; int lpos=l,rpos=mid+1; for(int i=l;i<=r;i++) { if(tree[dep][i]<sorted[mid]) tree[dep+1][lpos++]=tree[dep][i]; else if(tree[dep][i]==sorted[mid]&&same>0) { tree[dep+1][lpos++]=tree[dep][i]; same--; } else tree[dep+1][rpos++]=tree[dep][i]; toleft[dep][i]=toleft[dep][l-1]+lpos-l; } build(l,mid,dep+1); build(mid+1,r,dep+1);}int query(int L,int R,int l,int r,int dep,int k){ if(l==r) return tree[dep][l]; int mid=(L+R)/2; int cnt=toleft[dep][r]-toleft[dep][l-1]; if(cnt>=k) { int newl=L+toleft[dep][l-1]-toleft[dep][L-1]; int newr=newl+cnt-1; return query(L,mid,newl,newr,dep+1,k); } else { int newr=r+toleft[dep][R]-toleft[dep][r]; int newl=newr-(r-l-cnt); return query(mid+1,R,newl,newr,dep+1,k-cnt); }}int main(){ int T_T,n,m; scanf("%d",&T_T); while(T_T--) { scanf("%d%d",&n,&m); for(int i=1;i<=n;i++) { scanf("%d",sorted+i); tree[0][i]=sorted[i]; } sort(sorted+1,sorted+1+n); build(1,n,0); int l,r,k; while(m--) { scanf("%d%d%d",&l,&r,&k); printf("%d\n",query(1,n,l,r,0,k)); } } return 0;}
Hdoj 2665 kth number