mirror of
https://github.com/xlucn/PAT.git
synced 2026-10-31 06:37:38 +08:00
25 lines
1.2 KiB
HTML
25 lines
1.2 KiB
HTML
<!DOCTYPE html>
|
|
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
|
|
<h1>1104. Sum of Number Segments (20)</h1>
|
|
<div id="problemContent">
|
|
<p>
|
|
Given a sequence of positive numbers, a <i>segment</i> is defined to be a consecutive subsequence. For example, given the sequence {0.1, 0.2, 0.3, 0.4}, we have 10 segments: (0.1) (0.1, 0.2) (0.1, 0.2, 0.3) (0.1, 0.2, 0.3, 0.4) (0.2) (0.2, 0.3) (0.2, 0.3, 0.4) (0.3) (0.3, 0.4) (0.4).
|
|
</p>
|
|
<p>Now given a sequence, you are supposed to find the sum of all the numbers in all the segments. For the previous example, the sum of all the 10 segments is 0.1 + 0.3 + 0.6 + 1.0 + 0.2 + 0.5 + 0.9 + 0.3 + 0.7 + 0.4 = 5.0.
|
|
</p>
|
|
<p><b>
|
|
Input Specification:
|
|
</b></p>
|
|
<p>Each input file contains one test case. For each case, the first line gives a positive integer N, the size of the sequence which is no more than 10<sup>5</sup>. The next line contains N positive numbers in the sequence, each no more than 1.0, separated by a space.</p>
|
|
<p><b>
|
|
Output Specification:
|
|
</b></p>
|
|
<p>For each test case, print in one line the sum of all the numbers in all the segments, accurate up to 2 decimal places.</p>
|
|
<b>Sample Input:</b><pre>
|
|
4
|
|
0.1 0.2 0.3 0.4
|
|
</pre>
|
|
<b>Sample Output:</b><pre>
|
|
5.00
|
|
</pre>
|
|
</div> |