#include <bits/stdc++.h>
#include <iostream>
#include <cmath>
#include <iomanip>
#include <vector>
#include <map>
#include <stack>
#include <queue>
#include <set>
using namespace std;
#define ll long long
#define pb push_back
#define el '\n'
#define mpair make_pair
#define MASK(i) (1LL << (i))
#define BIT(mask, i) (((mask) >> (i)) & 1)
#define fi first
#define se second
#define all(v) v.begin(), v.end()
/* Author: Pham Gia Phuoc */
const ll MOD = (ll)(1e9) + 7LL;
template <class T1, class T2>
void add(T1 &a, T2 b){
a += b;
if(a >= MOD) a -= MOD;
}
template <class T1, class T2>
void sub(T1 &a, T2 b){
a -= b;
if(a < 0) a += MOD;
}
template <class T1, class T2>
bool minimize(T1 &a, T2 b){
if(a > b){a = b; return true;} return false;
}
template <class T1, class T2>
bool maximize(T1 &a, T2 b){
if(a < b){a = b; return true;} return false;
}
/** END OF TEMPLATE. DRINK A CUP OF COFFEE BEFORE READING MY CODE **/
const int MAX = (int)(1e6) + 10;
const ll INF = (ll) 1e18 + 67LL;
const int oo = (int)(1e9 + 7);
const int NUM_BIT = 62;
#define FOR(i, a, b) for(int i = a; i <= b; i++)
#define FORD(i, a, b) for(int i = a; i >= b; i--)
int n, a[MAX];
void init(){
cin >> n;
FOR(i, 1, n) cin >> a[i];
}
namespace subtask1{
bool check(){
return n <= 1e3;
}
const int MAXN = (int)(1e3) + 10;
vector <int> cur[MAXN];
int dp[MAXN];
void solve(){
FOR(i, 1, n){
FOR(j, 1, i){
cur[i].push_back(j);
}
sort(cur[i].begin(), cur[i].end());
cur[i].resize(unique(cur[i].begin(), cur[i].end()) - cur[i].begin());
}
dp[0] = 0;
FOR(i, 1, n){
dp[i] = dp[i - 1] + 1;
FORD(j, i - 1, 1){
if(a[j] > a[j + 1]) break;
if(a[j] == a[i]){
minimize(dp[i], dp[j - 1] + 1);
continue;
}
int cnt = upper_bound(cur[j - 1].begin(), cur[j - 1].end(), a[i] - 1) - lower_bound(cur[j - 1].begin(), cur[j - 1].end(), a[j] + 1);
if(cnt != 0) continue;
minimize(dp[i], dp[j - 1] + 1);
}
}
cout << dp[n];
}
}
void solve(){
if(subtask1::check()){subtask1::solve(); return;}
}
int main(){
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define test "test"
// freopen(test".inp", "r", stdin);
// freopen(test".out", "w", stdout);
srand(time(0));
int t = 1;
while(t--){
init();
solve();
}
return 0;
}
/*** ROAD TO VOI 2025 ***/
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
344 KB |
Output is correct |
2 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
344 KB |
Output is correct |
2 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
344 KB |
Output is correct |
2 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
344 KB |
Output is correct |
2 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |