Problem 1021.
Here is my solution:
#include <stdio.h>

int main()
{
  long N, K, i, j, temp;
  short flag=0;

  scanf("%ld",&N);
  long *in=new long (N+1);
  for(i=0;i<N;i++) scanf("%ld",&in[i]);

  scanf("%ld",&K);
  temp = in[N-1];
  long *out=new long (K+1);
  for(i=0;i<K;i++) scanf("%ld",&out[i]);

  in[N-1]=temp;
  for(i=0;i<N;i++){
  for(j=0;j<K;j++)
  {
    if((in[i]+out[j])==10000) flag=1;
  }
  }
  if(flag) printf("YES");
  else printf("NO");
  delete [] in;
  delete [] out;
  return 0;
}