无聊学了一下珂朵莉树
珂朵莉树好哇,是可以维护区间x次方和查询的高效数据结构。
思想大致就是一个暴力(相对而言)的树形数据结构
lxl毒瘤太强了,发明了ODT算法(Old Driver Tree老司机算法)
这里有一个大佬ACDreamer的题解
附上链接https://www.luogu.org/blog/ACdreamer/solution-cf896c
还有一个B站的讲解视频
附上链接https://www.bilibili.com/video/av21651173
我不会用珂朵莉树,但是就是大致了解了一下吧
毕竟普及蒟蒻听不懂省选算法。
这里附上大佬的程序
#include<cstdio>
#include<set>
#include<vector>
#include<utility>
#include<algorithm>
#define IT set<node>::iterator
using std::set;
using std::vector;
using std::pair;
typedef long long LL;
const int MOD7 = 1e9 + ;
const int MOD9 = 1e9 + ;
const int imax_n = 1e5 + ; LL pow(LL a, LL b, LL mod)
{
LL res = ;
LL ans = a % mod;
while (b)
{
if (b&) res = res * ans % mod;
ans = ans * ans % mod;
b>>=;
}
return res;
} struct node
{
int l,r;
mutable LL v;
node(int L, int R=-, LL V=):l(L), r(R), v(V) {}
bool operator<(const node& o) const
{
return l < o.l;
}
}; set<node> s; IT split(int pos)
{
IT it = s.lower_bound(node(pos));
if (it != s.end() && it->l == pos) return it;
--it;
int L = it->l, R = it->r;
LL V = it->v;
s.erase(it);
s.insert(node(L, pos-, V));
return s.insert(node(pos, R, V)).first;
} void add(int l, int r, LL val=)
{
IT itl = split(l),itr = split(r+);
for (; itl != itr; ++itl) itl->v += val;
} void assign_val(int l, int r, LL val=)
{
IT itl = split(l),itr = split(r+);
s.erase(itl, itr);
s.insert(node(l, r, val));
} LL rank(int l, int r, int k)
{
vector<pair<LL, int> > vp;
IT itl = split(l),itr = split(r+);
vp.clear();
for (; itl != itr; ++itl)
vp.push_back(pair<LL,int>(itl->v, itl->r - itl->l + ));
std::sort(vp.begin(), vp.end());
for (vector<pair<LL,int> >::iterator it=vp.begin();it!=vp.end();++it)
{
k -= it->second;
if (k <= ) return it->first;
}
return -1LL;
} LL sum(int l, int r, int ex, int mod)
{
IT itl = split(l),itr = split(r+);
LL res = ;
for (; itl != itr; ++itl)
res = (res + (LL)(itl->r - itl->l + ) * pow(itl->v, LL(ex), LL(mod))) % mod;
return res;
} int n, m;
LL seed, vmax; LL rnd()
{
LL ret = seed;
seed = (seed * + ) % MOD7;
return ret;
} LL a[imax_n]; int main()
{
scanf("%d %d %lld %lld",&n,&m,&seed,&vmax);
for (int i=; i<=n; ++i)
{
a[i] = (rnd() % vmax) + ;
s.insert(node(i,i,a[i]));
}
s.insert(node(n+, n+, ));
int lines = ;
for (int i =; i <= m; ++i)
{
int op = int(rnd() % ) + ;
int l = int(rnd() % n) + ;
int r = int(rnd() % n) + ;
if (l > r)
std::swap(l,r);
int x, y;
if (op == )
x = int(rnd() % (r-l+)) + ;
else
x = int(rnd() % vmax) +;
if (op == )
y = int(rnd() % vmax) + ;
if (op == )
add(l, r, LL(x));
else if (op == )
assign_val(l, r, LL(x));
else if (op == )
printf("%lld\n",rank(l, r, x));
else
printf("%lld\n",sum(l, r, x, y));
}
return ;
}