杭电ACM1003题目意思

来源:百度知道 编辑:UC知道 时间:2024/09/22 05:25:46
Problem Description
Given a sequence a[1],a[2],a[3]......a[n], your job is to calculate the max sum of a sub-sequence. For example, given (6,-1,5,4,-7), the max sum in this sequence is 6 + (-1) + 5 + 4 = 14.

Input
The first line of the input contains an integer T(1<=T<=20) which means the number of test cases. Then T lines follow, each line starts with a number N(1<=N<=100000), then N integers followed(all the integers are between -1000 and 1000).

Output
For each test case, you should output two lines. The first line is "Case #:", # means the number of the test case. The second line contains three integers, the Max Sum in the sequence, the start position of the sub-sequence, the end position of the sub-sequence. If there are more than one result, output the first one. Output a blank line between two cases.

Sample Input
2
5 6 -1 5 4 -7
7 0 6 -1 1 -6 7 -5

Sample Output
Case 1:
14 1 4

应该说是最大和的子序列,就是一个序列取它连续的一段数,要求和最大。

呵呵,你没有理解case1输入数据的意思啊~
5 6 -1 5 4 -7
第一个5是表示这个test的序列长度,于是后面就输入了6 -1 5 4 -7这5个数字~
于是最大和是14,从6到4没有错。

最大和子序列用动规求解。很经典的动规

最大和序列 14 表示最大值
1 ,4 是下标 , 表示从第一个 , 到第四个 的和有最大值( 14 )
一道动态规划题 。