#include<bits/stdc++.h>
using namespace std;
#define int int64_t
#define i32 signed
#define X first
#define Y second
#define pb push_back
using pii = pair<int,int>;
#define vt vector
#define sz(x) ((int)(x).size())
#define all(x) (x).begin(), (x).end()
#define f0r(i,a,b) for(auto i = (a); i != (b); i++)
#define r0f(i,a,b) for(auto i = (a); i >= (b); i--)
#define debug(x) {auto _x=x;cerr<<#x<<": "<<_x<<'\n';};
//walk with fixed l and moving r
//the adjacent deev is the starting point
vt<vt<int>> dp;
int n;
i32 maximum_deevs(vt<i32> y) {
n = sz(y);
dp = vt<vt<int>> (n+5, vt<int> (n+5));
f0r(i,1,n+1) dp[i][i] = dp[i][i+1] = 1;
r0f(l,n,1) {
int uuu = l+1;
//[uuu+1, r-1]
for(int r = l+2; r <= n; r++) {
int ha = y[r]-y[l], hb = y[uuu]-y[l];
int hc = r-l, hd = uuu-l;
//ha/hc > hb / hd to be seen
if(ha*hd > hb*hc) {
dp[l][r] = max({dp[l][r-1], dp[l+1][r], dp[l][uuu] + dp[uuu+1][r-1]});
uuu = r;
} else {
dp[l][r] = max({dp[l+1][r], dp[l][uuu] + dp[uuu+1][r], dp[l][r-1]});
}
}
}
return dp[1][n];
}
