zoukankan      html  css  js  c++  java
  • CodeForces 569A 第六周比赛C踢

    C - C
    Time Limit:2000MS     Memory Limit:262144KB     64bit IO Format:%I64d & %I64u

    Description

    Little Lesha loves listening to music via his smartphone. But the smartphone doesn't have much memory, so Lesha listens to his favorite songs in a well-known social network InTalk.

    Unfortunately, internet is not that fast in the city of Ekaterinozavodsk and the song takes a lot of time to download. But Lesha is quite impatient. The song's duration is T seconds. Lesha downloads the first S seconds of the song and plays it. When the playback reaches the point that has not yet been downloaded, Lesha immediately plays the song from the start (the loaded part of the song stays in his phone, and the download is continued from the same place), and it happens until the song is downloaded completely and Lesha listens to it to the end. For q seconds of real time the Internet allows you to download q - 1 seconds of the track.

    Tell Lesha, for how many times he will start the song, including the very first start.

    Input

    The single line contains three integers T, S, q (2 ≤ q ≤ 1041 ≤ S < T ≤ 105).

    Output

    Print a single integer — the number of times the song will be restarted.

    Sample Input

    Input
    5 2 2
    Output
    2
    Input
    5 4 7
    Output
    1
    Input
    6 2 3
    Output
    1

    Hint

    In the first test, the song is played twice faster than it is downloaded, which means that during four first seconds Lesha reaches the moment that has not been downloaded, and starts the song again. After another two seconds, the song is downloaded completely, and thus, Lesha starts the song twice.

    In the second test, the song is almost downloaded, and Lesha will start it only once.

    In the third sample test the download finishes and Lesha finishes listening at the same moment. Note that song isn't restarted in this case.

    题解:

    题目大意:一个人下载歌,每q个时间单位能下载q-1个时间单位的歌,歌的长度为T,下到S的时候开始播放,如果歌还没下完且放到了还未下载的地方,则重头开始放,问一共要放多少次

    题目分析:一开始从s开始,设下了cur秒后听和下的进度相同,则 s + (q - 1) / q * t = t,解得t = q * s,然后从头开始,设t'秒后进度相同,则(q - 1) / q * t' + cur = t',解得t' = t* q,可见直接拿第一次进度相同的时间乘q就是接下来每次进度相同的时间

    #include <iostream>
    using namespace std;
    int main()
    {
        long long t,s,q,total=1;
            cin>>t>>s>>q;
            if(t<=s) cout<<"1"<<endl;
                else
                {
                    while(t>s)
                {
                   s=s*q;
                   total++;
                }
                }
            cout<<total-1<<endl;
    
    }
  • 相关阅读:
    Windows 常见错误总结
    Windows 常用快捷方式
    【Linux】wget: command not found的两种解决方法
    【Linux】VirtualBox虚拟网络配置
    【Linux】启动Tomcat遇到Neither the JAVA_HOME nor the JRE_HOME environment variable is defined
    【REDIS】 redis-cli 命令
    【Charles】使用Charles时,抓不到包的情况。
    【Gradle】Downloading https://services.gradle.org/distributions/gradle-3.3-bin.zip 失败
    【LINUX】SHELL syntax error:unexpected end of file
    motan源码分析七:序列化
  • 原文地址:https://www.cnblogs.com/hfc-xx/p/4748974.html
Copyright © 2011-2022 走看看