NYOJ 外星人的供给战--710

#include<stdio.h>#include<stdlib.h>#include<math.h>struct node{double l,r;}num[10005];int cmp(const void *a,const void *b){return (*(node *)a).l-(*(node *)b).l;}int main(){int k,i,j;scanf("%d",&k);while(k--){int n,r,x,y;double t;scanf("%d %d",&n,&r);for(i=0;i<n;i++){scanf("%d %d",&x,&y);t=sqrt(r*r-y*y);num[i].l=x-t;num[i].r=x+t;}qsort(num,n,sizeof(num[0]),cmp);    //int count=1;int b=num[0].r;        int sum=1;        for(i=1;i<n;i++{          if(num[i].l>b)  {            sum++;            b=num[i].r;          }          else           {            if(num[i].r<b) b=num[i].r;          }        }printf("%d\n",sum);}return 0;}