hdu 1087 最长上升序列和 dp

Super Jumping! Jumping! Jumping!

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 56910    Accepted Submission(s): 26385

Problem Description

Nowadays,
a kind of chess game called “Super Jumping! Jumping! Jumping!” is very
popular in HDU. Maybe you are a good boy, and know little about this
game, so I introduce it to you now.

The
game can be played by two or more than two players. It consists of a
chessboard（棋盘）and some chessmen（棋子）, and all chessmen are marked by a
positive integer or “start” or “end”. The player starts from start-point
and must jumps into end-point finally. In the course of jumping, the
player will visit the chessmen in the path, but everyone must jumps from
one chessman to another absolutely bigger (you can assume start-point
is a minimum and end-point is a maximum.). And all players cannot go
backwards. One jumping can go from a chessman to next, also can go
across many chessmen, and even you can straightly get to end-point from
start-point. Of course you get zero point in this situation. A player is
a winner if and only if he can get a bigger score according to his
jumping solution. Note that your score comes from the sum of value on
the chessmen in you jumping path.
Your task is to output the maximum value according to the given chessmen list.

 

Input

Input contains multiple test cases. Each test case is described in a line as follow:
N value_1 value_2 …value_N
It is guarantied that N is not more than 1000 and all value_i are in the range of 32-int.
A test case starting with 0 terminates the input and this test case is not to be processed.

 

Output

For each case, print the maximum according to rules, and one line one case.

 

Sample Input

3 1 3 2

4 1 2 3 4

4 3 3 2 1

0

 

Sample Output

4

10

3

 

题意：有N个数字构成的序列，求最大递增子段和，即递增子序列和的最大值，思路就是定义dp[i]，表示以a[i]结尾的最大递增子段和，双重for循环，每次求出以a[i]结尾的最大递增子段和。

 

#include<iostream>
#include<string.h>
using namespace std;
int a[],dp[];
int max(int a,int b)
{
  return a>b?a:b;
}
int main()
{
  int n;
  while(cin>>n&&n!=)
  {
    for(int i=;i<n;i++)
      cin>>a[i];
    memset(dp,,sizeof(dp));
    dp[]=a[];
    for(int i=;i<n;i++)
    {
      for(int j=;j<i;j++)
      {
        if(a[i]>a[j])
          dp[i]=max(dp[i],dp[j]+a[i]);
      }
      dp[i]=max(dp[i],a[i]);

    }
    int ans=dp[];
    for(int i=;i<n;i++)
      ans=max(ans,dp[i]);
    cout<<ans<<endl;
  }
  return ;
}