poj 1836 dp lis

2015/2/12

最长上升子序列

一开始没看明白就埋头乱搞。

两次lis 取max 就提交（wa）了

其实  

7

1 2 3 4 3 2 1

输出是

7

这样子，都明白了吧= = 

做法：还是lis两遍 然后是 dp1[i ] + dp2[ j]  i <ｊ取ｍａｘ

#include<map>
#include<queue>
#include<stack>
#include<cmath>
#include<vector>
#include<climits>
#include<stdio.h>
#include<string.h>
#include<iostream>
#include<algorithm>

using namespace std;
typedef long long ll;  

#define mod 10007
#define lson pos<<1,l,mid
#define sc(n) scanf("%d",&n)
#define rson pos<<1|1,mid+1,r
#define pr(n) printf("%d\n",n)
#define met(n,m) memset(n, m, sizeof(n))
#define F(x,y,i) for(int i = x;i > y; i--)
#define f(x,y,i) for(int i = x;i < y; i++)
#define ff(x,y,i) for(int i = x;i <= y; i++)
#define FF(x,y,i) for(int i = x;i >= y; i--) 

const int N=100500;
const int inf = INT_MAX;

int Max(int a,int b)
{
	return a>b?a:b;
}

int Min(int a,int b)
{
	return  a<b?a:b;
}


double s[1005];
int dp1[1005];
int dp2[1005];
int main()  
{  
    int n, m, tot, x;
    while(~scanf("%d",&n))
    {
    	int minn;
    	f(0,n,i)
		{
			scanf("%lf",&s[i]);
		} 
		
		f(0,n,i)dp1[i] = 1;
		
		f(0,n,i)
		f(0,i,j)
		{
			if(s[i] > s[j])
			{
				dp1[i] =  Max(dp1[i],dp1[j] + 1);
			}
		}
		
	
			f(0,n,i)dp2[i] = 1;
		for(int i = n-1;i >= 0; i--)
		{
			for(int j = n-1;j > i; j--)
			{
				if(s[i] > s[j])
				{
					dp2[i] =  Max(dp2[i],dp2[j] + 1);
				}
			}
			
		}
		
		int maxn = 0;
		
		f(0,n,i)
		{
			for(int j = i+1;j < n; j++)
			{
				maxn = Max(maxn,dp1[i]+dp2[j]);
			}
		}
		
		
	
		
		printf("%d\n",n - maxn);
		    	
    }
    return 0;  
}