zoukankan      html  css  js  c++  java
  • Codeforces Round #240 (Div. 2) C Mashmokh and Numbers


    Mashmokh and Numbers

    It's holiday. Mashmokh and his boss, Bimokh, are playing a game invented by Mashmokh.

    In this game Mashmokh writes sequence of n distinct integers on the board. Then Bimokh makes several (possibly zero) moves. On the first move he removes the first and the second integer from from the board, on the second move he removes the first and the second integer of the remaining sequence from the board, and so on. Bimokh stops when the board contains less than two numbers. When Bimokh removes numbers x and yfrom the board, he gets gcd(x, y) points. At the beginning of the game Bimokh has zero points.

    Mashmokh wants to win in the game. For this reason he wants his boss to get exactly k points in total. But the guy doesn't know how choose the initial sequence in the right way.

    Please, help him. Find n distinct integers a1, a2, ..., an such that his boss will score exactly k points. Also Mashmokh can't memorize too huge numbers. Therefore each of these integers must be at most 109.

    Input

    The first line of input contains two space-separated integers n, k (1 ≤ n ≤ 105; 0 ≤ k ≤ 108).

    Output

    If such sequence doesn't exist output -1 otherwise output n distinct space-separated integers a1, a2, ..., an (1 ≤ ai ≤ 109).

    Sample test(s)
    input
    5 2
    output
    1 2 3 4 5
    input
    5 3
    output
    2 4 3 7 1
    input
    7 2
    output
    -1

    题意:找出一组数列,满足每相邻的两个数的最大公因数和为给定的值。

     sl:无以言状的水题,最终挂了,为什么呢,我把最后一个数字写的太小了。在知道直接0走起。

    相邻两个数字互素。利用这点很容易求出答案。 

      1 #include<cstdio>

     2 #include<cstring>
     3 #include<algorithm>
     4 #include<queue>
     5 using namespace std;
     6 typedef long long LL;
     7 const int MAX = 200;
     8 int main()
     9 {
    10     int n,k;
    11     while(scanf("%d %d",&n,&k)==2)
    12     {
    13         if(n==1&&k!=0) printf("-1 ");
    14         else if(n==1&&k==0) printf("1 ");
    15         else if(n/2>k) printf("-1 ");
    16         else
    17         {
    18             int a=1,b=2;
    19             int t=n/2; t*=2int x=n/2;
    20             int last=k-(x-1);
    21             for(int i=1;i<x;i++)
    22             {
    23                 if(a!=last&&b!=last&&a!=2*last&&b!=2*last)
    24                 {
    25                     if(i==1) printf("%d %d",a,b),a+=2, b+=2;
    26                     else printf(" %d %d",a,b),a+=2, b+=2;
    27                 }
    28                 else
    29                 {
    30                     while(a==last||b==last||a==2*last||b==2*last)
    31                     a+=2, b+=2;
    32                     if(i==1) printf("%d %d",a,b),a+=2, b+=2;
    33                     else printf(" %d %d",a,b),a+=2, b+=2;
    34 
    35                 }
    36             }
    37             if(x!=1&&last!=1) printf(" %d %d",2*last,last);
    38             else if(last!=1&&x==1) printf("%d %d",2*last,last);
    39             else if(x!=1&&last==1) printf(" 99999997 99999998");
    40             else if(last==1&&x==1) printf("99999997 99999998");
    41             if(n%2) printf(" 1000000000");
    42             printf(" ");
    43         }
    44     }
    45     return 0;
    46 }
  • 相关阅读:
    存储过程参数传递
    iCkeck插件
    单点登录
    SQL数据库默认实例与命名实例的区别
    IE浏览器重复提交ajax请求有缓存
    IE里Iframe的Cookie问题解决办法总结
    微信公众服务号开发
    解析url参数含有特殊字符的情况
    使用客户端控件展示增删改查操作
    修改网站web.config后出现奇怪问题找不到网页
  • 原文地址:https://www.cnblogs.com/acvc/p/3649948.html
Copyright © 2011-2022 走看看