C - Triangle Partition HDU - 6300-几何+思维

• C - Triangle Partition

•  HDU - 6300
• 题意：给3*n个点组成n个三角形不相邻，并且没有三点共线，直接按照x大小排序相邻选择三个即可

• #include<bits/stdc++.h>
  using namespace std;
  #define maxn 10050
  struct node
  {
      int x,y,id;
  } point[maxn];
  bool cmp(node a,node b)
  {
      if(a.x==b.x)return a.y<b.y;
      return a.x<b.x;
  }
  int t,n;
  int main()
  {
      scanf("%d",&t);
      while(t--)
      {
          scanf("%d",&n);
          for(int i=1; i<=3*n; i++)
          {
              scanf("%d%d",&point[i].x,&point[i].y);
              point[i].id=i;
          }
          sort(point+1,point+3*n+1,cmp);
          for(int i=1;i<=3*n;i+=3)
          printf("%d %d %d\n",point[i].id,point[i+1].id,point[i+2].id);
      }
      return 0;
  }