poj 3666

题意：

给定一个序列，以最小代价将其变成单调不增或单调不减序列，这里的代价看题目公式。

#include <iostream>
#include <cstdio>
#include <iomanip>
#include <string>
#include <cstdlib>
#include <cstring>
#include <queue>
#include <set>
#include <vector>
#include <map>
#include <algorithm>
#include <cmath>
#include <stack>
#include <stdlib.h>
#include <stdio.h>

#define INF 0x3f3f3f3f
#define LINF 0x3f3f3f3f3f3f3f3f
#define ll long long
#define ull unsigned long long
#define uint unsigned int
#define l(x) (x<<1)
#define r(x) (x<<1|1)
#define ms(a,b) memset(a,b,sizeof(a))

using namespace std;

int n, a[2222], c[2222], len, dp[2222][2222],mmin,ans;

int main() {
	ios::sync_with_stdio(false);
	cin >> n;
	for (int i = 1; i <= n; i++) {
		cin >> a[i];
		c[i] = a[i];
	}
	sort(c + 1, c + n + 1);
	len = unique(c + 1, c + n + 1) - c - 1;
	for (int i = 1; i <= n; i++) {
		mmin = INF;
		for (int j = 1; j <= len; j++) {
			mmin = min(mmin, dp[i - 1][j]);
			dp[i][j] = mmin + abs(a[i] - c[j]);
		}
	}
	ans = INF;
	for (int i = 1; i <= len; i++)
		ans = min(dp[n][i], ans);

	cout << ans << endl;

	return 0;
}