**Topic Connection: zoj2112**

Give n points, two operations, Q: Ask for the number of k large in [L,r], C: Change the i digit X

Dynamic Inquiry K Large, using a tree-like array to modify and query prefixes and.

Because the given space is small, you can make n points into a static chairman tree, and then for the modified value, in the other chairman of the tree to modify, query the same time query the two chairmen tree can be.

#include <cstdio> #include <cstring> #include <algorithm>using namespace std; #pragma comment (linker, "/stack:1024000000,1024000000") struct node{int L, r, Num;} p[2500000];//all nodes, p[i].l of the left son of the first node, p[i].num node I nodes have a number of points int n, q, cnt; int a[50010], b[10010][3];//a is the initial input, B is the operand int s[ 60010], M;//discretization of the array, and the number of discrete mint tree[50010], s[50010];//tree dynamic chairman tree, using a tree array to modify/query prefixes and, S Static chairman Tree, retain the initial n-point prefix and. int use[50010]; int lowbit (int x) {return x & x;} int build (int l,int r) {int x = cnt++, mid = (l+r)/2; P[x].num = 0; if (L < r) {P[X].L = build (L,mid); P[X].R = Build (Mid+1,r); } return x;} int search1 (int x) {int low = 0, Mid, high = m-1; while (low <= high) {mid = (low + high)/2; if (s[mid] = = x) return mid; else if (S[mid] < x) Low = mid + 1; else high = mid-1; }}int Update (int y,int k,int num) {int root = cnt++, x = root; int L = 0, R = m-1, mid; P[x].num = P[y].num + num; while (L < r) {mid = (l+r)/2; if (k <= mid) {r = Mid; P[X].L = cnt++; P[X].R = P[Y].R; x = P[X].L; y = p[y].l; } else {L = mid + 1; P[X].L = P[Y].L; P[X].R = cnt++; x = P[X].R; y = P[Y].R; } p[x].num = P[y].num + num; } return root;} void init () {int k, I, J; Sort (s,s+m); m = Unique (s,s+m)-S; CNT = 0; S[0] = build (0,m-1); for (i = 1; I <= n; i++) s[i] = Update (S[I-1],SEARCH1 (A[i]), 1); for (i = 1; I <= n; i++) tree[i] = s[0];} int sum (int i) {int sum = 0; while (i) {sum + = p[p[use[i]].L].num; I-= lowbit (i); } return sum;} void query (int ll,int rr,int k) {int num, I, l = 0, R = m-1, Mid, rt_l = S[ll-1], Rt_r = S[RR]; for (i = ll-1; i; i-= Lowbit (i)) use[i] = Tree[i]; for (i = RR; i; I-= Lowbit (i)) use[i] = Tree[i]; while (L < r) {num = SUM (RR)-sum (LL-1) + p[p[rt_r].l].num-p[p[rt_l].l].num; Mid = (L + r)/2; if (num >= k) {r = Mid; for (i = ll-1; i; i-= Lowbit (i)) use[i] = p[Use[i]].L; for (i = RR; i; I-= Lowbit (i)) use[i] = p[Use[i]].L; rt_l = p[rt_l].l; Rt_r = p[Rt_r].l; } else {L = mid + 1; K-= num; for (i = ll-1; i; i-= Lowbit (i)) use[i] = p[Use[i]].R; for (i = RR; i; I-= Lowbit (i)) use[i] = p[Use[i]].R; rt_l = p[rt_l].r; Rt_r = p[Rt_r].r; }} printf ("%d\n", S[l]);} int main () {int T, I, J, K1, K2; int L, R; Char str[10]; scanf ("%d", &t); while (t--) {scanf ("%d%d", &n, &q); m = 0; for (i = 1; I <= n; i++) { scanf ("%d", &a[i]); s[m++] = A[i]; } for (i = 0; i < Q; i++) {scanf ("%s", str); if (str[0] = = ' Q ') {scanf ("%d%d", &b[i][0], &b[i][1], &b[i][2]); } else {B[i][0] =-1; scanf ("%d%d", &b[i][1], &b[i][2]); s[m++] = b[i][2]; }} init (); for (i = 0; i < Q; i++) {if (b[i][0] = = 1) {k1 = Search1 (a[b[i][1]); K2 = Search1 (b[i][2]); for (j = b[i][1]; j <= N; j + = Lowbit (j)) {Tree[j] = update (TREE[J],K1,-1); TREE[J] = update (tree[j],k2,1); } a[b[i][1]] = b[i][2]; } else {query (b[i][0],b[i][1],b[i][2]); }}} return 0;}

Zoj2112--dynamic rankings (tree-like array + chairman tree)