我要长高

http://www.acm.uestc.edu.cn/problem.php?pid=1685

单调队列优化DP

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <queue>
#include <algorithm>
#include <vector>
#include <cstring>
#include <stack>
#include <cctype>
#include <utility>   
#include <map>
#include <string>  
#include <climits> 
#include <set>
#include <string>    
#include <sstream>
#include <utility>   
#include <ctime>
#include <bitset>

using std::priority_queue;
using std::vector;
using std::swap;
using std::stack;
using std::sort;
using std::max;
using std::min;
using std::pair;
using std::map;
using std::string;
using std::cin;
using std::cout;
using std::set;
using std::queue;
using std::string;
using std::stringstream;
using std::make_pair;
using std::getline;
using std::greater;
using std::endl;
using std::multimap;
using std::deque;
using std::unique;
using std::lower_bound;
using std::random_shuffle;
using std::bitset;
using std::upper_bound;

typedef long long LL;
typedef unsigned long long ULL;
typedef pair<int, int> PAIR;
typedef multimap<int, int> MMAP;
typedef LL TY;
typedef long double LF;

const int MAXN(200010);
const int MAXM(100010);
const int MAXE(100010);
const int MAXK(6);
const int HSIZE(31313);
const int SIGMA_SIZE(26);
const int MAXH(19);
const int INFI((INT_MAX-1) >> 1);
const ULL BASE(31);
const LL LIM(10000000);
const int INV(-10000);
const int MOD(20100403);
const double EPS(1e-7);
const LF PI(acos(-1.0));

template<typename T> void checkmax(T &a, T b){if(b > a) a = b;}
template<typename T> void checkmin(T &a, T b){if(b < a) a = b;}
template<typename T> T ABS(const T &a){return a < 0? -a: a;}

int value[110];
int que[110];
int front, back;

int table[2][110];
int pow2[110];

int main()
{
	int N, C;
	for(int i = 0; i <= 100; ++i)
		pow2[i] = i*i;
	while(~scanf("%d%d", &N, &C))
	{
		int cur = 0, last = 1;
		int h1, h2;
		scanf("%d", &h1);
		for(int i = 1; i < h1; ++i)
			table[last][i] = INFI;
		for(int i = h1; i <= 100; ++i)
			table[last][i] = pow2[i-h1];
		for(int i = 1; i < N; ++i)
		{
			scanf("%d", &h2);
			for(int j = 1; j <= 100; ++j)
				table[cur][j] = INFI;
			front = 0;
			back = -1;
			for(int j = h1; j < h2; ++j)
			{
				int tv = table[last][j]-C*j;
				while(front <= back && tv <= value[back]) --back;
				value[++back] = tv;
			}
			for(int j = h2; j <= 100; ++j)
			{
				int tv = table[last][j]-C*j;
				while(front <= back && tv <= value[back]) --back;
				value[++back] = tv;
				checkmin(table[cur][j], pow2[j-h2]+C*j+value[front]);
			}
			front = 0;
			back = -1;
			for(int j = 100; j >= h2; --j)
			{
				int tv = table[last][j]+C*j;
				while(front <= back && tv <= value[back]) --back;
				value[++back] = tv;
				checkmin(table[cur][j], pow2[j-h2]-C*j+value[front]);
			}
			h1 = h2;
			swap(cur, last);
		}
		int ans = INFI;
		for(int i = h1; i <= 100; ++i)
			checkmin(ans, table[last][i]);
		printf("%d\n", ans);
	}
	return 0;
}