#include<stdio.h>
#include<stdlib.h>



int main (void)
{
    int N,M,i;
    int A[100];
    int judge=0;

    scanf("%d %d",&N,&M);
    //scanf("%s",c);

    for(i=0;i<N;i++){
        scanf("%d ",&A[i]);
        //scanf("%s",c);
    }

    if(A[M-1]<1/4*M){
        judge=1;
    }


    if(judge==0){
        printf("Yes");
    }else{
        printf("No");
    }
  
    return 0;

}
