zoukankan      html  css  js  c++  java
  • codeforces 630K Indivisibility (容斥原理)

    IT City company developing computer games decided to upgrade its way to reward its employees. Now it looks the following way. After a new game release users start buying it actively, and the company tracks the number of sales with precision to each transaction. Every time when the next number of sales is not divisible by any number from 2 to 10 every developer of this game gets a small bonus.

    A game designer Petya knows that the company is just about to release a new game that was partly developed by him. On the basis of his experience he predicts that n people will buy the game during the first month. Now Petya wants to determine how many times he will get the bonus. Help him to know it.

    Input

    The only line of the input contains one integer n (1 ≤ n ≤ 1018) — the prediction on the number of people who will buy the game.

    Output

    Output one integer showing how many numbers from 1 to n are not divisible by any number from 2 to 10.

    Examples
    input
    12
    
    output
    2


    题意:给你一个数n,找出1~n范围内不被2~10整除的数的个数。

    思路:这题可以用容斥原理,找到2~10里的4个素数2,3,5,7,然后用容斥原理就行了。


    #include<iostream>
    #include<stdio.h>
    #include<stdlib.h>
    #include<string.h>
    #include<math.h>
    #include<vector>
    #include<map>
    #include<set>
    #include<queue>
    #include<stack>
    #include<string>
    #include<algorithm>
    using namespace std;
    typedef long long ll;
    #define inf 99999999
    #define pi acos(-1.0)
    int main()
    {
        ll n,ans;
        while(scanf("%I64d",&n)!=EOF)
        {
            ans=n-(n/2+n/3+n/5+n/7-n/6-n/10-n/14-n/15-n/21-n/35+n/30+n/42+n/70+n/105-n/210      );
            printf("%I64d
    ",ans);
        }
        return 0 ;
    }


  • 相关阅读:
    Windows 10 版本 1507 中的新 AppLocker 功能
    github 查询
    Facebook Paper使用的第三方库
    C#如何使用右下角托盘图标notifyIcon
    C#如何设置窗体不能修改大小
    C#如何让Listbox支持多选
    C#如何开发多语言支持的Winform程序
    C#如何发布项目 发布软件
    C#如何编辑tab选项卡
    C#如何把写好的类编译成dll文件
  • 原文地址:https://www.cnblogs.com/herumw/p/9464551.html
Copyright © 2011-2022 走看看