#include <bits/stdc++.h>
using namespace std;
#ifdef tabr
#include "library/debug.cpp"
#else
#define debug(...)
#endif
int maximum_deevs(vector<int> y) {
int n = (int) y.size();
vector<vector<int>> dp(n + 1, vector<int>(n + 1));
function<int(int, int)> solve = [&](int l, int r) {
if (l >= r) {
return 0;
}
if (dp[l][r]) {
return dp[l][r];
}
int pos = (int) (max_element(y.begin() + l, y.begin() + r) - y.begin());
dp[l][r] = 1;
int lst = pos;
pair<int, int> a = make_pair(1, 0);
for (int i = pos - 1; i >= l; i--) {
auto b = make_pair(y[pos] - y[i], pos - i);
if (1LL * a.first * b.second >= 1LL * a.second * b.first) {
a = b;
dp[l][r] += solve(i + 1, lst);
lst = i;
}
}
dp[l][r] += solve(l, lst);
lst = pos;
a = make_pair(1, 0);
for (int i = pos + 1; i < r; i++) {
auto b = make_pair(y[pos] - y[i], i - pos);
if (1LL * a.first * b.second >= 1LL * a.second * b.first) {
a = b;
dp[l][r] += solve(lst + 1, i);
lst = i;
}
}
dp[l][r] += solve(lst + 1, r);
dp[l][r] = max(dp[l][r], solve(l, pos) + solve(pos + 1, r));
return dp[l][r];
};
return solve(0, n);
}
#ifdef tabr
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
debug(maximum_deevs({6, 1, 5, 2, 3, 1}));
debug(maximum_deevs({0, 1, 2}));
return 0;
}
#endif
