12230-crossing rivers (probability)

Source: Internet
Author: User

Ultraviolet A 12230-crossing rivers

Question Link

A: Given several rivers, each river has a boat sailing back and forth. When a day goes out, the boat is in a random position. Now the expected time is required from A to B.

Train of Thought: The worst expectation for each river is that the ship has just driven 3l/V, and the best is to ship the ship directly L/V. The expectation is 4l/V/2 = 2L/v, the answer is the time when the land is migrated.

Code:

# Include <stdio. h> # include <string. h> int N; double D, P, L, V; int main () {int CAS = 0; while (~ Scanf ("% d % lf", & N, & D) & N | D) {While (n --) {scanf ("% lf ", & P, & L, & V); D = D-L + L * 2/V;} printf ("case % d: %. 3lf \ n ", ++ cas, d);} return 0 ;}


Contact Us

The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion; products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the content of the page makes you feel confusing, please write us an email, we will handle the problem within 5 days after receiving your email.

If you find any instances of plagiarism from the community, please send an email to: info-contact@alibabacloud.com and provide relevant evidence. A staff member will contact you within 5 working days.

A Free Trial That Lets You Build Big!

Start building with 50+ products and up to 12 months usage for Elastic Compute Service

  • Sales Support

    1 on 1 presale consultation

  • After-Sales Support

    24/7 Technical Support 6 Free Tickets per Quarter Faster Response

  • Alibaba Cloud offers highly flexible support services tailored to meet your exact needs.