HDU 2665.kth number-K smaller in no modification interval-persistence line segment tree (Chair tree) template

 

 

Kth number

Time Limit: 15000/5000 MS (Java/others) memory limit: 32768/32768 K (Java/Others)
Total submission (s): 16941 accepted submission (s): 5190

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 input1 10 1 1 4 2 3 5 6 7 8 9 0 1 3 2

 

Sample output2

 

Sourcehdu boys' open session-the question from whu is that the query interval is K small, and the line segment tree can be persisted. Before learning the data structure that can be persisted, I felt that this was a very big and amazing thing. After learning about it, I found that the problem was caused, So I updated it on the basis of the original line segment tree, supports querying historical versions. If you create a whole line segment tree every time you update it, it will be crazy, so you can simply open a new node and save the updated chain. This kind of thing still needs to be realized by yourself, come on, salted fish. Code:

1 // the k-th smaller part of the no-modification interval-persistent line segment tree (weight line segment tree + persistent) 2 # include <iostream> 3 # include <cstdio> 4 # include <cstring> 5 # include <algorithm> 6 # include <bitset> 7 # include <cassert> 8 # include <cctype> 9 # include <cmath> 10 # include <cstdlib> 11 # include <ctime> 12 # include <deque> 13 # include <iomanip> 14 # include <list> 15 # include <map> 16 # include <queue> 17 # include <set> 18 # include <stack> 19 # include <vector> 20 using namespace s TD; 21 typedef long ll; 22 typedef pair <int, int> PII; 23 24 const double Pi = ACOs (-1.0); 25 const double EPS = 1e-6; 26 const ll mod = 1e9 + 7; 27 const int INF = 0x3f3f3f; 28 const int maxn = 1e5 + 10; 29 const int maxm = 100 + 10; 30 # define IOS IOs:: sync_with_stdio (false); cin. tie (0); cout. tie (0); 31 # define lson L, M 32 # define rson m + 1, R 33 34 int A [maxn], B [maxn], sum [maxn <5], L [maxn <5], R [maxn <5]; // sum Line Segment Values saved in the tree: l left son, r right son 35 int n, m, SZ = 0; 36 37 void build (Int & RT, int L, int R) // create an empty tree 38 {39 RT = ++ SZ; sum [RT] = 0; // dynamic start point, initial value 0, empty tree 40 if (L = r) {41 return; 42} 43 44 int M = (L + r)> 1; 45 build (L [RT], lson); 46 build (R [RT], rson); 47} 48 49 void Update (int pr, Int & RT, int L, int R, int X) 50 {51 RT = ++ SZ; sum [RT] = sum [pr] + 1; // insert sequence, inherit the previous line segment tree, and then directly use single point + 1 to perform 52 l [RT] = L [pr]; R [RT] = R [pr]; 53 If (L = r) {54 return; 55} 56 57 Int M = (L + r)> 1; 58 If (x <= m) Update (L [pr], L [RT], lson, X ); // because no update is required on the right side, the 59 else Update (R [pr], R [RT], rson, x) on the left is overwritten ); 60} 61 62 int query (int pr, int RT, int L, int R, int X) // query the line segment tree between l and R in the R insertion minus L-1-1 insertion {64 if (L = r) {65 return l; 66} 67 // because we have created a weight line segment tree, you can directly search for 68 int M = (L + r)> 1; 69 int now = sum [L [RT]-sum [L [pr]; // now is the left subtree new tree-old tree 70 If (now> = X) return query (L [pr], L [RT], lson, x); 71 else return query (R [pr], R [RT], rson, X-now); 72} 73 74 int RT [maxn]; 75 76 int main () 77 {78 int T; 79 scanf ("% d", & T); 80 while (t --) {81 scanf ("% d", & N, & M ); 82 SZ = 0; 83 for (INT I = 1; I <= N; I ++) {84 scanf ("% d", & A [I]); 85 B [I] = A [I]; 86} 87 sort (B + 1, B + 1 + n); // sort all values first to remove duplicates, used to create a weight line segment tree. The content stored in the weight line segment tree is the number of values. 88 int d = unique (B + 1, B + 1 + n)-(B + 1); 89 build (RT [0], 1, D ); 90 for (INT I = 1; I <= N; I ++) {// insert a 91 int x = lower_bound (B + 1, B + 1 + D, a [I])-B; 92 Update (RT [I-1], RT [I], 1, D, X ); 93} 94 for (INT I = 1; I <= m; I ++) {95 int L, R, K; 96 scanf ("% d ", & L, & R, & K); 97 printf ("% d \ n", B [query (RT L-1], RT [R], 1, D, k)]); 98} 99} 100 return 0; 101}

 

 

 

You come to the world to see the sun and the interesting world outside.

 

 

 

HDU 2665.kth number-K smaller in no modification interval-persistence line segment tree (Chair tree) template