#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const ll INF = LLONG_MAX / 4;
// Segment-tree-beats: support range_max_assign (chmax) and range_min query
struct Beats {
struct Node { ll mn, snd_mn, cnt_mn, lazy_add; };
int n;
vector<Node> st;
Beats(int _n): n(_n), st(4*n) {}
void apply_min(int p, ll x) {
if (st[p].mn >= x) return;
st[p].mn = x;
// lazy_add not changed, we only push upward
}
void push(int p) {
for (int k: {p<<1, p<<1|1}) {
apply_min(k, st[p].mn);
}
}
void pull(int p) {
auto &l = st[p<<1], &r = st[p<<1|1], &u = st[p];
if (l.mn < r.mn) {
u.mn = l.mn;
u.cnt_mn = l.cnt_mn;
u.snd_mn = min(l.snd_mn, r.mn);
} else if (r.mn < l.mn) {
u.mn = r.mn;
u.cnt_mn = r.cnt_mn;
u.snd_mn = min(r.snd_mn, l.mn);
} else {
u.mn = l.mn;
u.cnt_mn = l.cnt_mn + r.cnt_mn;
u.snd_mn = min(l.snd_mn, r.snd_mn);
}
}
void build(int p, int l, int r, const vector<ll>& base) {
if (l == r) {
st[p].mn = base[l];
st[p].snd_mn = INF;
st[p].cnt_mn = 1;
return;
}
int m = (l+r)/2;
build(p<<1, l, m, base);
build(p<<1|1, m+1, r, base);
pull(p);
}
// set all values in [i,j] to at least x
void range_chmax(int p, int l, int r, int i, int j, ll x) {
if (i>r || j<l || st[p].mn >= x) return;
if (i<=l && r<=j && st[p].snd_mn > x) {
apply_min(p, x);
return;
}
push(p);
int m = (l+r)/2;
range_chmax(p<<1, l, m, i, j, x);
range_chmax(p<<1|1, m+1, r, i, j, x);
pull(p);
}
ll range_min(int p, int l, int r, int i, int j) {
if (i>r || j<l) return INF;
if (i<=l && r<=j) return st[p].mn;
push(p);
int m = (l+r)/2;
return min(range_min(p<<1, l, m, i, j),
range_min(p<<1|1, m+1, r, i, j));
}
};
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
int n, K;
cin >> n >> K;
vector<ll> a(n+1);
for (int i = 1; i <= n; i++) cin >> a[i];
vector<ll> dp_prev(n+1, INF), dp_cur(n+1, INF);
dp_prev[0] = 0;
// base k=1: prefix max
for (int i = 1; i <= n; i++) dp_prev[i] = max(dp_prev[i-1], a[i]);
for (int k = 2; k <= K; k++) {
Beats st(n+1);
st.build(1, 0, n, dp_prev);
int left = k;
for (int i = k; i <= n; i++) {
// enforce max(a[j+1..i]) using range_chmax
st.range_chmax(1, 0, n, k-1, i-1, *max_element(a.begin()+left, a.begin()+i+1));
dp_cur[i] = st.range_min(1, 0, n, k-1, i-1);
}
dp_prev.swap(dp_cur);
fill(dp_cur.begin(), dp_cur.end(), INF);
}
cout << dp_prev[n] << '\n';
return 0;
}
