日志统计（桶思想）

解题思路:桶储存，内部部依次比较，达到了K退出当前循环，这样做可以大大提高效率

参考代码:

#include <iostream>
using namespace std;
#include <vector>
#include <algorithm>
int main()
{
   int N,D,K;
   cin>>N>>D>>K;
   //桶储存，内部部依次比较，达到了K退出当前循环，这样做可以大大提高效率
   vector< int> all(N);
   //桶
    vector< vector<int> > nums(100002);
    int a=0,b=0;
    for (int i=0;i<N;i++ )
    {
        cin>>a>>b;
        nums[b].push_back(a);
    }
     for (int i=0;i<100002;i++)
     {
         //特殊情况，K==1
          if (K==1&&nums[i].size()>=1)
          {
             cout<<i<<"\n";
             continue;
          }
         if (nums[i].size()>=1)
         {
               int out=1;
               bool backnow=false;
             for (int j=0;j<nums[i].size();j++ )
             {
                  for (int m=0;m<nums[i].size()&&m!=j;m++ )
                  {
                      if (abs(nums[i][j]-nums[i][m])<D)
                      {
                            if (++out>=K)
                            {
                                cout<<i<<"\n";
                                backnow=true;
                                break;
                            }
                      }
                  }
                   if (backnow)
                   {
                      break;
                   }
             }
         }
     }
    return 0;
}