zoukankan      html  css  js  c++  java
  • Codeforces Round #256 (Div. 2) E. Divisors 因子+dfs

    E. Divisors
    time limit per test
    2 seconds
    memory limit per test
    256 megabytes
    input
    standard input
    output
    standard output

    Bizon the Champion isn't just friendly, he also is a rigorous coder.

    Let's define function f(a), where a is a sequence of integers. Function f(a) returns the following sequence: first all divisors of a1 go in the increasing order, then all divisors of a2 go in the increasing order, and so on till the last element of sequence a. For example,f([2, 9, 1]) = [1, 2, 1, 3, 9, 1].

    Let's determine the sequence Xi, for integer i (i ≥ 0): X0 = [X] ([X] is a sequence consisting of a single number X), Xi = f(Xi - 1) (i > 0). For example, at X = 6 we get X0 = [6], X1 = [1, 2, 3, 6], X2 = [1, 1, 2, 1, 3, 1, 2, 3, 6].

    Given the numbers X and k, find the sequence Xk. As the answer can be rather large, find only the first 105 elements of this sequence.

    Input

    A single line contains two space-separated integers — X (1 ≤ X ≤ 1012) and k (0 ≤ k ≤ 1018).

    Output

    Print the elements of the sequence Xk in a single line, separated by a space. If the number of elements exceeds 105, then print only the first 105 elements.

    Examples
    input
    6 1
    output
    1 2 3 6 
    input
    4 2
    output
    1 1 2 1 2 4 
    input
    10 3
    output
    1 1 1 2 1 1 5 1 1 2 1 5 1 2 5 10 

     题意:给你一个数,分解k次;

       每次将每个数分解成它的质因数,个数>=1e5不输出;

    思路:枚举质因数,dfs求解,详见代码;

    #include<bits/stdc++.h>
    using namespace std;
    #define ll long long
    #define pi (4*atan(1.0))
    const int N=2e5+10,M=4e6+10,inf=1e9+10;
    ll x,k,flag;
    set<ll>s;
    set<ll>::iterator it;
    ll p[N],len;
    void dfs(ll x,ll step)
    {
        if(step>k)return;
        if(flag>=100000)return;
        if(step==k||x==1)
        {
            if(flag>=100000)return;
            printf("%lld ",x);
            flag++;
            return;
        }
        for(ll i=0;i<len;i++)
        {
            ll v=p[i];
            if(v>x)break;
            //cout<<v<<"cccc"<<x<<endl;
            if(x%v==0)
            dfs(v,step+1);
        }
    }
    int main()
    {
        scanf("%lld%lld",&x,&k);
        len=0;
        for(ll i=1;i*i<=x;i++)
        {
            if(i*i==x)
            p[len++]=i;
            else if(x%i==0)
            p[len++]=i,p[len++]=x/i;
        }
        sort(p,p+len);
        flag=0;
        dfs(x,0);
        return 0;
    }
  • 相关阅读:
    【转载】分析商品日均销量(DMS)对促销商品选择的意义
    日志备份和差异备份还原中的常见问题示例(转自&邹建)
    SQL Server 2000中的完整备份、差异备份操作
    数据库差异备份与增量备份的不同之处
    差异备份和还原操作方法(转)
    SQL备份(全)
    Microsoft SQL2000 错误代码 (@@error)
    图解SQL的inner join(join)、left join、right join、full outer join、union、union all的区别
    arm-none-linux-gnueabi-gcc command not found
    关于ST-Link的internal command error问题的解决方法
  • 原文地址:https://www.cnblogs.com/jhz033/p/5845067.html
Copyright © 2011-2022 走看看