【CF896C】Willem, Chtholly and Seniorious

ODT模板题，ODT适合随机数据下具有维护区间推平操作的序列维护题目，时间复杂度较为玄学。。

代码如下

#include <bits/stdc++.h>
#define pb push_back
#define mp make_pair
#define all(x) x.begin(),x.end()
using namespace std;
const int maxn=1e5+10;
const int mod=1e9+7;
typedef long long LL;
LL fpow(LL a,LL b,LL c){
	LL ret=1%c;
	for(;b;b>>=1,a=a*a%c)if(b&1)ret=ret*a%c;
	return ret;
}

int n,m;
LL seed,vmax;
LL rnd(){
	LL ret=seed;
	seed=(seed*7+13)%mod;
	return ret;
}
struct node{
	int l,r;
	mutable LL val;
	node(int x=0,int y=0,LL z=0):l(x),r(y),val(z){}
	bool operator<(const node &rhs)const{
		return this->l<rhs.l;
	}
};
set<node> s;
auto split(int pos){
	auto it=s.lower_bound(node(pos));
	if(it!=s.end()&&it->l==pos)return it;
	--it;
	int l=it->l,r=it->r;
	LL val=it->val;
	s.erase(it);
	s.insert(node(l,pos-1,val));
	return s.insert(node(pos,r,val)).first;
}
void add(int l,int r,LL x){
	auto itr=split(r+1),itl=split(l);
	for(auto it=itl;it!=itr;it++)it->val+=x;
}
void assign(int l,int r,LL x){
	auto itr=split(r+1),itl=split(l);
	s.erase(itl,itr);
	s.insert(node(l,r,x));
}
LL kth(int l,int r,int k){
	auto itr=split(r+1),itl=split(l);
	vector<pair<LL,int>> v;v.clear();
	for(auto it=itl;it!=itr;it++){
		v.pb(mp(it->val,it->r-it->l+1));
	}
	sort(all(v));
	for(auto p:v){
		k-=p.second;
		if(k<=0)return p.first; 
	}
	return -1;
}
LL sum(int l,int r,int x,int y){
	auto itr=split(r+1),itl=split(l);
	LL ret=0;
	for(auto it=itl;it!=itr;it++){
		ret=(ret+fpow(it->val%y,x,y)*(it->r-it->l+1)%y)%y;
	}
	return ret;
}

int main(){
	scanf("%d%d%lld%lld",&n,&m,&seed,&vmax);
	for(int i=1;i<=n;i++){
		s.insert(node(i,i,rnd()%vmax+1));
	}
	s.insert(node(n+1,n+1,0));
	
	while(m--){
		int opt=rnd()%4+1,l=rnd()%n+1,r=rnd()%n+1,x,y;
		if(l>r)swap(l,r);
		if(opt==3)x=rnd()%(r-l+1)+1;
		else x=rnd()%vmax+1;
		if(opt==4)y=rnd()%vmax+1;
		if(opt==1)add(l,r,x);
		else if(opt==2)assign(l,r,x);
		else if(opt==3)printf("%lld\n",kth(l,r,x));
		else if(opt==4)printf("%lld\n",sum(l,r,x,y));
	}
	
	return 0;
}