P2710 数列[fhq treap]

调了一辈子的fhq treap…

如果不会最大子段和

如果不会fhq treap

7个操作…
其中三个查询 单点查询其实可以和区间查询写成一个（

fhq treap 的修改操作大概就是 \(split\) 完了然后把修改区间的根 打上标记 等着下传就完事了…

那这题没了…我给个好一点的小数据…反正我照着这个调了挺久的…

.in
50 10
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 
GET 13
REVERSE 15 1
MAKE-SAME 1 1 3
REVERSE 21 8
GET-SUM 22 3
MAX-SUM 32 2
GET 8
DELETE 4 9
GET 36
REVERSE 34 2

.out
13
78
65
8
45

#include<cstdio>
#include<cstdlib>
#include<string>
#include<iostream>
int min(int x , int y) {
	return x < y ? x : y ;
}
int max(int x , int y) {
	return x > y ? x : y ;
}
void swap(int & x , int & y) {
	x ^= y ^= x ^= y ;
}

int read() {
	int x = 0 , f = 1 ;
	char c = getchar() ;
	while(c < 48 || c > 57) {
		if(c == '-') f = 0 ;
		c = getchar() ;
	}
	while(c >= 48 && c <= 57) {
		x = (x << 1) + (x << 3) + (c & 15) ;
		c = getchar() ;
	}
	return f ? x : -x ;
}

int n , m , rt , cnt ;
constexpr int N = 2e6 + 10 ;
constexpr int lim = 2333 ;
int a[N] ;
int rnd[N] , val[N] , sum[N] , sz[N] , ls[N] , rs[N] ;
int lmax[N] , rmax[N] , mx[N] ;
int tag[N] , rev[N] ;

void pushup(int o) {
	sz[o] = sz[ls[o]] + sz[rs[o]] + 1 ;
	sum[o] = sum[ls[o]] + sum[rs[o]] + val[o] ;
	lmax[o] = max(lmax[ls[o]] , sum[ls[o]] + max(0 , lmax[rs[o]]) + val[o]) ;
	rmax[o] = max(rmax[rs[o]] , sum[rs[o]] + max(0 , rmax[ls[o]]) + val[o]) ;
	mx[o] = max(0 , rmax[ls[o]]) + max(0 , lmax[rs[o]]) + val[o] ;
	if(ls[o]) mx[o] = max(mx[o] , mx[ls[o]]) ;
	if(rs[o]) mx[o] = max(mx[o] , mx[rs[o]]) ;
}

void reverse(int o) {
	swap(ls[o] , rs[o]) ;
	swap(lmax[o] , rmax[o]) ;
	rev[o] ^= 1 ;
}

void cover(int o , int v) {
	val[o] = tag[o] = v ;
	sum[o] = v * sz[o] ;
	lmax[o] = rmax[o] = mx[o] = max(sum[o] , v) ;
}

void pushdown(int o) {
	if(rev[o]) {
		if(ls[o]) reverse(ls[o]) ;
		if(rs[o]) reverse(rs[o]) ;
		rev[o] ^= 1 ;
	}
	if(tag[o] != lim) {
		if(ls[o]) cover(ls[o] , tag[o]) ;
		if(rs[o]) cover(rs[o] , tag[o]) ;
		tag[o] = lim ;
	}
}

int newnode(int k) {
	++ cnt ;
	rnd[cnt] = rand() ;
	val[cnt] = sum[cnt] = k ;
	lmax[cnt] = rmax[cnt] = mx[cnt] = k ;
	sz[cnt] = 1 ;
	tag[cnt] = lim ;
	ls[cnt] = rs[cnt] = 0 ;
	return cnt ;
}

int merge(int x , int y) {
	if(! x || ! y) return x | y ;
	if(rnd[x] < rnd[y]) {
		pushdown(x) ;
		rs[x] = merge(rs[x] , y) ;
		pushup(x) ;
		return x ;
	} else {
		pushdown(y) ;
		ls[y] = merge(x , ls[y]) ;
		pushup(y) ;
		return y ;
	}
}

void split(int cur , int k , int & x , int & y) {
	if(! cur) {
		x = y = 0 ;
		return ;
	}
	pushdown(cur) ;
	if(sz[ls[cur]] < k) {
		split(rs[cur] , k - sz[ls[cur]] - 1 , x , y) ;
		rs[cur] = 0 ;
		pushup(cur) ;
		x = merge(cur , x) ;
	} else {
		split(ls[cur] , k , x , y) ;
		ls[cur] = 0 ;
		pushup(cur) ;
		y = merge(y , cur) ;
	}
}

int newrt(int len) {
	int _newrt = 0 ;
	for(int i = 1 ; i <= len ; i ++) _newrt = merge(_newrt , newnode(read())) ;
	return _newrt ;
}

void insert(int pos , int len) {
	int x , y ;
	split(rt , pos , x , y) ;
	rt = merge(merge(x , newrt(len)) , y) ;
}

void remove(int l , int r) {
	int x , y , z ;
	split(rt , l - 1 , x , z) ;
	split(z , r - l + 1 , y , z) ;
	rt = merge(x , z) ;
}

void rever(int l , int r) {
	int x , y , z ;
	split(rt , l - 1 , x , z) ;
	split(z , r - l + 1 , y , z) ;
	reverse(y) ;
	rt = merge(merge(x , y) , z) ;
}

void cover(int l , int r , int v) {
	int x , y , z ;
	split(rt , l - 1 , x , z) ;
	split(z , r - l + 1 , y , z) ;
	cover(y , v) ;
	rt = merge(merge(x , y) , z) ;
}

int query_sum(int l , int r) {
	int x , y , z ;
	split(rt , l - 1 , x , z) ;
	split(z , r - l + 1 , y , z) ;
	int res = sum[y] ;
	rt = merge(merge(x , y) , z) ;
	return res ;
}

int query_point(int pos) {
	int x , y , z ;
	split(rt , pos , x , z) ;
	split(x , pos - 1 , x , y) ;
	int res = val[y] ;
	rt = merge(merge(x , y) , z) ;
	return res ;
}

int query_max_sum(int l , int r) {
	int x , y , z ;
	split(rt , l - 1 , x , z) ;
	split(z , r - l + 1 , y , z) ;
	int res = mx[y] ;
	rt = merge(merge(x , y) , z) ;
	return res ;
}

int getopt(std :: string opt) {
	if(opt == "INSERT") return 1 ;
	if(opt == "DELETE") return 2 ;
	if(opt == "REVERSE") return 3 ;
	if(opt == "MAKE-SAME") return 4 ;
	if(opt == "GET-SUM") return 5 ;
	if(opt == "GET") return 6 ;
	if(opt == "MAX-SUM") return 7 ;
}


int main() {
	srand(19260817) ;
	n = read() , m = read() ;
	rt = newrt(n) ;
	while(m --) {
		std :: string s ;
		std :: cin >> s ;
		int opt = getopt(s) ;
		if(opt == 1) {
			int pos = read() , len = read() ;
			insert(pos , len) ;
		}
		if(opt == 2) {
			int pos = read() , len = read() ;
			remove(pos , pos + len - 1) ;
		}
		if(opt == 3) {
			int pos = read() , len = read() ;
			rever(pos , pos + len - 1) ;
		}
		if(opt == 4) {
			int pos = read() , len = read() , v = read() ;
			cover(pos , pos + len - 1 , v) ;
		}
		if(opt == 5) {
			int pos = read() , len = read() ;
			printf("%d\n" , query_sum(pos , pos + len - 1)) ;
		}
		if(opt == 6) printf("%d\n" , query_point(read())) ;
		if(opt == 7) {
			int pos = read() , len = read() ;
			printf("%d\n" , query_max_sum(pos , pos + len - 1)) ;
		}
	}
	return 0 ;
}