zoukankan      html  css  js  c++  java
  • HDU 1164 Eddy's research I(素数打表)

    Eddy's interest is very extensive, recently he is interested in prime number. Eddy discover the all number owned can be divided into the multiply of prime number, but he can't write program, so Eddy has to ask intelligent you to help him, he asks you to write a program which can do the number to divided into the multiply of prime number factor .

    Input
    The input will contain a number 1 < x<= 65535 per line representing the number of elements of the set.
    Output
    You have to print a line in the output for each entry with the answer to the previous question.
    Sample Input
    11
    9412
    Sample Output
    11
    2213*181

    题意:

    任何一个数都能拆分成质因子相乘。

    题解:

    把范围内的所有素数筛选出来,然后找就行了。

    #include<iostream>
    #include<cstdio>
    #include<algorithm>
    using namespace std;
    const int maxn=1e5+5;
    int prime[maxn];
    int is_prime[maxn];
    int sieve(int n)
    {
        int cnt=0;
        for(int i=0;i<=n;i++)
            is_prime[i]=true;
        is_prime[0]=is_prime[1]=false;
        for(int i=2;i<=n;i++)
        {
            if(is_prime[i])
            {
                prime[cnt++]=i;
                for(int j=2*i;j<=n;j+=i)
                    is_prime[j]=false;
            }
        }
        return cnt;
    }
    int main()
    {
        int k=sieve(65535);
        int n;
        while(cin>>n)
        {
            bool flag=true;
            for(int i=0;i<k;i++)
            {
                while(n&&n%prime[i]==0)
                {
                    n/=prime[i];
                    if(flag)
                    {
                        flag=false;
                        cout<<prime[i];
                    }
                    else
                        cout<<'*'<<prime[i];
                }
                if(!n)
                    break;
            }
            cout<<endl;
        }
        return 0;
    }
    
  • 相关阅读:
    记laravel项目,本地环境PHP7.1,线上PHP版本7.2,报错each函数废弃问题
    [教程] 《Mysql 实战 45 讲》
    PHP递归求和计算1加到n的和
    SSL原理
    PHP之抽象类与接口
    iOS调试之挂起线程
    iOS之Starfield
    iOS之透视效果
    CSS之框模型
    HTTP之CacheControl
  • 原文地址:https://www.cnblogs.com/orion7/p/7930979.html
Copyright © 2011-2022 走看看