#include<stdio.h>

int main() {
   int N, M;
   int A[N];
   int count = 0;
   float data;

   scanf("%d %d", &N, &M);

   for(int i = 0; i < N; i++) {
      scanf("%d", &A[i]);
      count += A[i];

   }

   data = count / (4 * M);
   if(A[M] >= data) {
      printf("Yes\n");

   }else {
      printf("No\n");

   }
   return 0;
}
