title
subtitle
latex: $O(n^2)$
$$
k^{k^{k^{k^{k^{k^{k^{k^{k^{k^{k^{k}}}}}}}}}}}
$$
#include <set>
#include <map>
#include <cmath>
#include <queue>
#include <stack>
#include <ctime>
#include <cstdio>
#include <bitset>
#include <cctype>
#include <cstring>
#include <cassert>
#include <cstring>
#include <iostream>
#include <algorithm>
using namespace std;
#define fi first
#define se second
#define rep(x,s,t) for(register int t_=t,x=s;x<t_;x++)
#define per(x,s,t) for(register int s_=s,x=(t)-1;x>=s_;x--)
#define travel(x) for(int I=last[x],to;I&&(to=e[I].to);I=e[I].nxt)
#define prt(x) cout<<#x<<":"<<x<<" "
#define prtn(x) cout<<#x<<":"<<x<<endl
#define y1 asfkagn
#define y2 fansfk
#define rank gkalsfm
#define hash gafgalsf
#define inf (1<<30)
#define INF (1ll<<61)
#define showtime printf("%f",1.0*clock()/CLOCKS_PER_SEC)
typedef long long ll;
typedef double db;
typedef pair<int,int> ii;
const long double pi=acos(-1);
template<class T>void sc(T &x)
{
int f=1;char c;x=0;
while(c=getchar(),c<48)if(c=='-')f=-1;
do x=x*10+(c^48);
while(c=getchar(),c>47);
x*=f;
}
template<class T>void nt(T x)
{
if(!x)return;
nt(x/10);
putchar('0'+x%10);
}
template<class T>void pt(T x)
{
if(x<0)x=-x,putchar('-');
if(!x)putchar('0');
else nt(x);
}
template<class T>void pts(T x)
{
pt(x);putchar(' ');
}
template<class T>void ptn(T x)
{
pt(x);putchar('\n');
}
template<class T>inline void Max(T &x,T y){if(x<y)x=y;}
template<class T>inline void Min(T &x,T y){if(x>y)x=y;}
int main()
{
// freopen("pro.in","r",stdin);
// freopen("chk.out","w",stdout);
return 0;
}