ccf201809-1 vegetables (out of code)

#include<stdio.h> 
#define N 1010
int a[N];
int b[N];
int main(){
 int n;
 scanf("%d", &n);
 for(int i=0; i<n; ++i){
  scanf("%d", &a[i]);
 }
 for(int i=1; i<n-1; ++i){
  b[i] = (a[i-1]+a[i]+a[i+1])/3;
 }
 b[0] = (a[0]+a[1])/2;
 b[n-1] = (a[n-2]+a[n-1])/2;
 for(int i=0; i<n; ++i){
  printf("%d ", b[i]);
 }
 return 0;
}