【dp专题1】hdu1087最大上升子段和 E

Super Jumping! Jumping! Jumping!

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：输入n，再输入n个数，找到在这n个数中最大的上升子段和

题意：这道题其实就是最长上升子序列的变形题，max_len数组由记录最长上升子序列长度变为记录最大上升子序列长度，

每次找完i左边的最大上升子序列长度后，再在结尾加上自身的数

#include<stdio.h>
#include<string.h>
#define N 1000+10

int max_len[N];
int num[N];

int main()
{
	int n;
	int i,j;
	int num_len,max;
	while(scanf("%d",&n),n != 0)
	{
		for(i = 1; i <= n; i ++)
			scanf("%d",&num[i]);
		max_len[1] = num[1];
		max = num[1];
		for( i = 1; i <= n; i ++)
		{
			num_len = 0;//记录i左边的最大上升子段和
			for(j = 1; j < i; j ++)//找到i左边的最大上升子段和
			{
				if(num[i] > num[j])
				{
					if(num_len < max_len[j])
						num_len = max_len[j];
				}
			}
			max_len[i] = num_len + num[i];
			if(max_len[i] > max)
				max = max_len[i];
		}
		printf("%d
",max);
	}
	return 0;
}