zoukankan      html  css  js  c++  java
  • Codeforces Round #466 (Div. 2) -A. Points on the line

    2018-02-25
    A. Points on the line
    time limit per test
    1 second
    memory limit per test
    256 megabytes
    input
    standard input
    output
    standard output

    We've got no test cases. A big olympiad is coming up. But the problemsetters' number one priority should be adding another problem to the round.

    The diameter of a multiset of points on the line is the largest distance between two points from this set. For example, the diameter of the multiset {1, 3, 2, 1} is 2.

    Diameter of multiset consisting of one point is 0.

    You are given n points on the line. What is the minimum number of points you have to remove, so that the diameter of the multiset of the remaining points will not exceed d?

    Input

    The first line contains two integers n and d (1 ≤ n ≤ 100, 0 ≤ d ≤ 100) — the amount of points and the maximum allowed diameter respectively.

    The second line contains n space separated integers (1 ≤ xi ≤ 100) — the coordinates of the points.

    Output

    Output a single integer — the minimum number of points you have to remove.

    Examples
    Input
    3 1
    2 1 4
    Output
    1
    Input
    3 0
    7 7 7
    Output
    0
    Input
    6 3
    1 3 4 6 9 10
    Output
    3
    Note

    In the first test case the optimal strategy is to remove the point with coordinate 4. The remaining points will have coordinates 1 and 2, so the diameter will be equal to 2 - 1 = 1.

    In the second test case the diameter is equal to 0, so its is unnecessary to remove any points.

    In the third test case the optimal strategy is to remove points with coordinates 1, 9 and 10. The remaining points will have coordinates 3, 4 and 6, so the diameter will be equal to 6 - 3 = 3.

    感想:本题逆向思考比较适合,之前的想法还是没过样例,后面的代码是错误的,先放着。现在写模拟题,最怕WA了但是不知道WA哪里,这种情况下,怎么才能快速找到bug或者怎么从一种思维模式中挣脱出来尝试新方法呢...

    code

     1 #include<cstring>
     2 #include<cmath>
     3 #include<algorithm>
     4 #include<cstdio>
     5 #include<vector>
     6 #include<queue>
     7 #include<iostream>
     8 using namespace std;
     9 int main()
    10 {
    11     int n,d;
    12     cin>>n>>d;
    13     int a[105];
    14     for(int i=0;i<n;i++)
    15      cin>>a[i];
    16     sort(a,a+n);    
    17     int ans=0;
    18     for(int i=0;i<n;i++)
    19     {
    20         int pos=i,t=0;
    21         while(a[pos]<=a[i]+d&&pos<n)   //默认a[i]前的数都已经被删除了 
    22         {
    23             pos++;
    24             t++;
    25         }
    26     
    27         ans=max(ans,t);
    28     }
    29     cout<<n-ans;     
    30 }

    wrong code(错了两次,还没改正)

     1 #include<string.h>
     2 #include<cmath>
     3 #include<cstdio>
     4 #include<algorithm>
     5 #include<iostream>
     6 #include<vector> 
     7 #include<queue>
     8 using namespace std;
     9 int main()
    10 {
    11     int n,d;
    12     int a[105];
    13     int b[105];
    14     while(~scanf("%d%d",&n,&d))
    15     {
    16         int ans=0; 
    17         memset(a,0,sizeof(a));
    18         memset(b,0,sizeof(b));  
    19         for(int i=0;i<n;i++)
    20           scanf("%d",&a[i]);
    21         sort(a,a+n);
    22         for(int i=0;i<n;i++)
    23          for(int j=0;j<n;j++)
    24           if(abs(a[i]-a[j])>d)
    25            b[a[i]]++;                  
    26         int r=n-1,l=0;
    27         while(a[r]-a[l]>d)
    28         {   
    29             if(b[a[r]]>b[a[l]])
    30             {
    31               r--;
    32               for(int i=0;i<n;i++)
    33                if(abs(a[r]-a[i])>d)       // 
    34                 b[a[i]]--;  
    35             }
    36             else
    37             {
    38               l++;
    39               for(int i=0;i<n;i++)
    40                if(abs(a[l]-a[i])>d)         //这两个地方是新添的 
    41                 b[a[i]]--;
    42             }
    43             ans++;      
    44         }
    45         printf("%d
    ",ans);
    46           
    47     }
    48 }
  • 相关阅读:
    跟我学Makefile(七)
    C++单例模式
    乘法逆元及求法
    推荐几个jetbrains全家桶好用的插件,同时作为备忘
    win32 获取本机网卡信息(MAC地址,IP地址等)
    centos7 安装 mysql-python时 报错 EnvironmentError: mysql_config not found
    VS2013 中使用 CxImage 库时用Unicode编码时出现链接错误
    剑指offer-二叉搜索树的后序遍历序列
    剑指offer-顺时针打印矩阵
    剑指offer-二叉树的镜像
  • 原文地址:https://www.cnblogs.com/LLbinGG/p/8469403.html
Copyright © 2011-2022 走看看