thought
Tree cover tree, like his name, is a tree cover another tree. Use an outer tree to maintain something like intervals. Then each node of the outer tree is an inner tree. That's it.
A template question
bzoj3196
thinking
This is a template problem of line tree set balance tree. The outer layer uses a line segment tree to maintain the section operation. Then each node of the line tree is a balance tree
Operation 1: query the number smaller than k from l to r, and then output + 1
Action 2: split the answer and find the maximum value of ranking less than or equal to k
Action 3: delete the original value first, and then add a new value
Operation 4: query the precursor in each sub interval, and the largest one is the precursor in the current interval
Operation 5: similar to operation 4, query the successor in each subinterval, and then the smallest one is the successor in the current interval.
PS: do not forget to change the value in the original array during operation 3, or you will make an error when you delete it later. 2 hours 2333 in this place
Code
/* * @Author: wxyww * @Date: 2018-12-11 08:29:48 * @Last Modified time: 2018-12-11 10:44:01 */ #include<cstdio> #include<iostream> #include<cstdlib> #include<cmath> #include<ctime> #include<bitset> using namespace std; typedef long long ll; #define ls TR[cur].ch[0] #define rs TR[cur].ch[1] const int N = 100000 + 100,INF = 2147483647; ll read() { ll x=0,f=1;char c=getchar(); while(c<'0'||c>'9') { if(c=='-') f=-1; c=getchar(); } while(c>='0'&&c<='9') { x=x*10+c-'0'; c=getchar(); } return x*f; } namespace treap { struct node { int val,siz,ch[2],id,cnt; }TR[N * 20]; void up(int cur) { TR[cur].siz = TR[ls].siz + TR[rs].siz + TR[cur].cnt; } int tot = 0; void rotate(int &cur,int f) { int son = TR[cur].ch[f]; TR[cur].ch[f] = TR[son].ch[f ^ 1]; TR[son].ch[f ^ 1] = cur; up(cur); cur = son; up(cur); } void insert(int &cur,int val) { if(!cur) { cur = ++tot; TR[cur].val = val; TR[cur].siz = TR[cur].cnt = 1; TR[cur].id = rand(); return; } TR[cur].siz++; if(val == TR[cur].val) int d = val > TR[cur].val; insert(TR[cur].ch[d],val); if(TR[TR[cur].ch[d]].id < TR[cur].id) rotate(cur,d); } void del(int &cur,int val) { if(!cur) return; if(TR[cur].val == val) { if(TR[cur].cnt > 1) if(!ls || !rs) rotate(cur,TR[rs].id < TR[ls].id); del(cur,val); return; } TR[cur].siz--; del(TR[cur].ch[val > TR[cur].val],val); } int Rank(int cur,int val) { int ans = 0; while(cur) { if(val < TR[cur].val) cur = ls; else if(val == TR[cur].val) return ans + TR[ls].siz; else ans += TR[ls].siz + TR[cur].cnt,cur = rs; } return ans; } int pred(int cur,int val) { if(!cur) return -INF; if(val > TR[cur].val) return max(pred(rs,val),TR[cur].val); else return pred(ls,val); } int nex(int cur,int val) { if(!cur) return INF; if(val < TR[cur].val) return min(nex(ls,val),TR[cur].val); else return nex(rs,val); } } using namespace treap; int tree[N << 2]; int a[N]; int n; void build(int rt,int l,int r) { if(l == r) { insert(tree[rt],a[l]); return; } int mid = (l + r) >> 1; for(int i = l;i <= r;++i) insert(tree[rt],a[i]); build(rt << 1,l,mid); build(rt << 1 | 1,mid + 1,r); } void delet(int rt,int l,int r,int pos,int c) { if(l == r) { insert(tree[rt],c); del(tree[rt],a[pos]); return; } insert(tree[rt],c); del(tree[rt],a[pos]); int mid = (l + r) >> 1; if(pos <= mid) delet(rt << 1,l,mid,pos,c); else delet(rt << 1 | 1,mid + 1,r,pos,c); } int getrank(int rt,int l,int r,int L,int R,int val) { if(L <= l && R >= r) return Rank(tree[rt],val); int mid = (l + r) >> 1; int ans = 0; if(L <= mid) ans += getrank(rt << 1,l,mid,L,R,val); if(R > mid) ans += getrank(rt << 1 | 1,mid + 1,r,L, R,val); return ans; } int getpred(int rt,int l,int r,int L,int R,int val) { if(L <= l && R >= r) return pred(tree[rt],val); int mid = (l + r) >> 1; int ans = -INF; if(L <= mid) ans = max(ans,getpred(rt << 1,l,mid,L,R,val)); if(R > mid) ans = max(ans,getpred(rt << 1 | 1,mid + 1,r,L, R,val)); return ans; } int getnex(int rt,int l,int r,int L,int R,int val) { if(L <= l && R >= r) return nex(tree[rt],val); int mid = (l + r) >> 1; int ans = INF; if(L <= mid) ans = min(ans,getnex(rt << 1,l,mid,L,R,val)); if(R > mid) ans = min(ans,getnex(rt << 1 | 1,mid + 1,r,L,R,val)); return ans; } int MAX = -INF; int getkth(int L,int R,int x) { int l = 0,r = INF; int ans = 0; while(l <= r) { int mid = (l + r) >> 1; if(getrank(1,1,n,L,R,mid) + 1<= x) ans = mid,l = mid + 1; else r = mid - 1; } return ans; } int main() { n = read(); int m = read(); for(int i = 1;i <= n;++i) a[i] = read(); build(1,1,n); while(m--) { int opt = read(); if(opt == 1) { int l = read(),r = read(),k = read(); printf("%d\n",getrank(1,1,n,l,r,k) + 1); } if(opt == 2) { int l = read(),r = read(),k = read(); printf("%d\n",getkth(l,r,k)); } if(opt == 3) { int pos = read(),k = read(); delet(1,1,n,pos,k); a[pos] = k;//!!! } if(opt == 4) { int l = read(),r = read(),k = read(); printf("%d\n",getpred(1,1,n,l,r,k)); } if(opt == 5) { int l = read(),r = read(),k = read(); printf("%d\n",getnex(1,1,n,l,r,k)); } } return 0; }