Chairman Tree Template

Use this template can direct a off HDU 2665 Kth number This problem!

/* Chairman tree for interval k large Template: * Template Special Description: * Each tree is maintained from 1 to CNT subscript information */#include <stdio.h> #include <algorithm> #define    Maxn 100010using namespace Std;int T, N, M, tot, A[MAXN], B[MAXN], CNT;     T is the number of input CAs, N is the number of arrays of the original array, M is the number of queries, tot for the achievement of the original node//a, B is used for discretization of the sequence, its unique after the number of elements of cntstruct N {int ls, RS, w;} tree[30 * MAXN];    LS is the left son node subscript, RS is the right son node subscript, W for this interval within the number of elements int ROOTS[MAXN];    Roots record the root node of each tree subscript int build_tree (int l, int r) {//First build an empty tree int newnode = tot++;    TREE[NEWNODE].W = 0;        if (L = r) {int mid = (L + r)/2;        Tree[newnode].ls = Build_tree (L, mid);    Tree[newnode].rs = Build_tree (mid + 1, R); } return newnode;}    int updata (int rt, int pos, int val) {//rt is the root node, plus val value int newnode = tot++, tmp = NewNode in pos position;    TREE[NEWNODE].W = Tree[rt].w + val;    int L = 1, r = CNT;        while (L < r) {int mid = (L + r)/2;            if (pos <= mid) {tree[newnode].ls = tot++;            tree[newnode].rs = tree[rt].rs; NewNode = TREe[newnode].ls;            RT = Tree[rt].ls;        R = Mid;            } else {tree[newnode].ls = Tree[rt].ls;            tree[newnode].rs = tot++;            NewNode = tree[newnode].rs;            RT = Tree[rt].rs;        L = mid + 1;    } TREE[NEWNODE].W = Tree[rt].w + val; } return TMP;    int query (int rt1, int rt2, int k) {//Ask the root node to be rt1,rt2 between two trees respectively the value of the K-large int l = 1, r = CNT;        while (L < r) {int mid = (L + r)/2;        int tmp = TREE[TREE[RT2].LS].W-TREE[TREE[RT1].LS].W;            if (tmp >= k) {rt1 = Tree[rt1].ls;            Rt2 = Tree[rt2].ls;        R = Mid;            } else {k-= tmp;            Rt1 = tree[rt1].rs;            Rt2 = tree[rt2].rs;        L = mid + 1; }} return L;}    int main () {//freopen ("in.in", "R", stdin);    Freopen ("Out.out", "w", stdout);    scanf ("%d", &t);        while (t--) {//read in data groups scanf ("%d%d", &n, &m); for (int i = 1; i <= N;            i++) {scanf ("%d", &a[i]);        B[I-1] = A[i];        } sort (b, B + N);     CNT = unique (b, B + N)-B;        discretization of tot = 0;        Roots[0] = Build_tree (1, CNT);            for (int i = 1; I <= n; i++) {int tmp = (int) (Lower_bound (b, B + CNT, a[i])-B) + 1;    Roots[i] = Updata (roots[i-1], TMP, 1);        Build on the last time} int l,r,k; for (int i=0;i<m;i++) {scanf ("%d%d%d", &l,&r,&k);//read in for L and R interval k large number int tmp = query (roo            TS[L-1],ROOTS[R],K);        printf ("%d\n", b[tmp-1]); }} return 0;}

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Chairman Tree Template