ccf201912-2回收站选址（满分代码）

#include 
#include  
#include 
using namespace std;
#define N 1010
struct node{
 int x, y;
}a[N];
node b[N], c[N], d[N];
int e[N];
bool cmp1(node a, node b){
 if(a.x != b.x) return a.x < b.x;
 else return a.y < b.y;
}
bool cmp2(node a, node b){
 if(a.y != b.y) return a.y < b.y;
 else return a.x < b.x;
}
int main(){
 memset(e, 0, sizeof(e));
 int n, i, j;
 scanf("%d", &n);
 for(i=0; i<n; ++i){
  scanf("%d%d", &a[i].x, &a[i].y);
  b[i].x = a[i].x; b[i].y = a[i].y;
 }
 sort(a, a+n, cmp1); sort(b, b+n, cmp2);
 int k = 0;
 for(i=1; i<n-1; ++i){
  if(a[i-1].x==a[i].x && a[i].x==a[i+1].x && a[i-1].y+1==a[i].y && a[i].y==a[i+1].y-1){
   c[k].x = a[i].x; c[k].y = a[i].y; ++k;
  }
 }
 int h = 0;
 for(i=1; i<n-1; ++i){
  if(b[i-1].y==b[i].y && b[i].y==b[i+1].y && b[i-1].x+1==b[i].x && b[i].x==b[i+1].x-1){
   d[h].x = b[i].x; d[h].y = b[i].y; ++h;
  }
 }
 sort(d, d+h, cmp1);
 int w = 0;
 for(i=0; i<k; ++i){
  for(j=0; j<h; ++j){
   if(c[i].x==d[j].x && c[i].y==d[j].y){
    b[w].x = c[i].x; b[w].y = c[i].y; ++w;
   }
  }
 }
 int count;
 for(i=0; i<w; ++i){
  count = 0;
  for(j=0; j<n; ++j){
   if(b[i].x+1 == a[j].x){
    if(b[i].y+1 == a[j].y) count++;
    if(b[i].y-1 == a[j].y) count++;
   }
   if(b[i].x-1 == a[j].x){
    if(b[i].y+1 == a[j].y) count++;
    if(b[i].y-1 == a[j].y) count++;
   }
  }
  e[count]++;
 }
 for(i=0; i<=4; ++i){
  printf("%d\n", e[i]);
 }
 return 0;
}