【POJ 1836】 Alignment

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#define esp 1e-8

using namespace std;

double dp[1111];//左向右LIS
double dpn[1111];//右向左LIS
double ht[1111];//记录士兵身高
int lenup[1111],lendown[1111];//左向右对应位置LIS长度 右向左对应位置LIS长度
int tp;

int dcmp(double x)
{
    return x < -esp? -1: x > esp;
}

int main()
{
    int n,i,j,mm;
    scanf("%d",&n);

    for(i = 0; i < n; ++i)
    {
        scanf("%lf",&ht[i]);
    }

    tp = 1;
    dp[0] = 0;
    for(i = 0; i < n; ++i)
    {
        for(j = tp; j > 0; --j)
        {
            if(dcmp(ht[i]-dp[j-1]) > 0)
            {
                if(j == tp) dp[tp++] = ht[i];
                else dp[j] = dcmp(ht[i] - dp[j]) < 0? ht[i]: dp[j];
            }
        }
        lenup[i] = tp-1;
    }

    tp = 1;
    dp[n-1] = 0;
    for(i = n-1; i >= 0; --i)
    {
         for(j = tp; j > 0; --j)
        {
            if(dcmp(ht[i]-dpn[j-1]) > 0)
            {
                if(j == tp) dpn[tp++] = ht[i];
                else dpn[j] = dcmp(ht[i] - dpn[j]) < 0? ht[i]: dpn[j];
            }
        }
        lendown[i] = tp-1;
    }
    mm = n;
    for(i = 0; i < n-1; ++i)//枚举找最少出队人数
    {
        mm = min(mm,n-(lenup[i]+lendown[i+1]));
    }
    printf("%d\n",mm);
    return 0;
}