题目链接:http://acm.timus.ru/problem.aspx?space=1&num=1902
1902. Neo-Venice
Time limit: 1.0 second
Memory limit: 64 MB
Memory limit: 64 MB
Mars
was the first planet colonized by humans. After a long terraforming
process
its appearance has changed completely. From the red desert it has become
a
blue planet covered by water. There was so much water that some of the
cities were built not on land, but on stilts over the water. The most
famous one was Neo-Venice. There are canals instead of
roads and numerous gondolas instead of cars in this city. All this
attracts huge crowds of tourists from the Earth to Neo-Venice.
The most popular activities among them are boat excursions. Gondolas are
steered by young
girls who can not only bring tourists through the canals but also tell
them
about the history of the city or sing a song along the way. Due to their
love for the water these girls are called undines.
The undine Anna has just received a license to steer a gondola.
Tomorrow she will carry tourists on excursion to the St. Peter's canal.
This canal is narrow, but many popular routes are passing through it, so
there are always a lot of gondolas. Anna is afraid that her excitement may
lead to a crash with another gondola during the excursion. However, all
undines are trained to steer the gondola smoothly and
with the same speed, so the only threat comes from gondolas sailing in
the opposite direction. Anna knows the schedule of her colleagues and when
she herself will enter the canal. Now she wants to know exactly when she
will encounter other gondolas, in order to be extra careful around them.
Input
The first line of the input contains integers n, t and s. n is
the number of undines who will go through the St. Peter’s canal in the
opposite direction (1 ≤ n ≤ 100).
t is the time needed for the gondola to sail through the entire length of the canal (1 ≤ t ≤ 100).
s is the moment of time at which the Anna's gondola will enter the canal (360 ≤ s
≤ 1200).
The second line contains integers s1, …, sn that define the moments of time at which
the gondolas of Anna’s colleagues will appear on the opposite side of the
canal.
s − t < s1 < … < sn < s + t.
Output
Output n numbers that are the points of time when Anna will meet her colleagues, with
absolute or relative error no more than 10−6. Numbers should be
separated with spaces or line feeds.
Sample
input | output |
---|---|
2 60 600 600 630 |
630.000000 645.000000 |
Problem Author: Denis Dublennykh
Problem Source: Ural Championship 2012
Problem Source: Ural Championship 2012
Tags: none
Difficulty: 87 Printable version Submit solution Discussion (2)
My submissions All submissions (1691) All accepted submissions (1003) Solutions rating (804)
My submissions All submissions (1691) All accepted submissions (1003) Solutions rating (804)
分析:
如图,A船从河道一端出发(河道只能走一条船),走过这条河所需时间为t(每条船都相同),当前所在位置时的时间为s,在接下来一段时间里,可能会在对面出现n只船只(不会同时出现),出现时的时间为Si(1<=i<=n),给出序列S,求出两船相遇时的时间。
Ti=(s+t+S[i])/2
注意Ti得是double类型的,可改为:(s+t+S[i])*1.0/2
代码:
By LFENG
#include<stdio.h>
#include<math.h> int main() { int n,t,s,i,se[103]; double temp; scanf("%d %d %d",&n,&t,&s); for(i=0;i<n;i++) scanf("%d",&se[i]); for(i=0;i<n;i++) { temp=(s+t+se[i])*1.0/2; printf("%.6lf\n",temp); } return 0; } |