#include <bits/stdc++.h>
using namespace std;
int main(void){
    int n,k;
    cin>>n>>k;
    vector<int>a(n);
    for(int i=0;i<n;i++)cin>>a[i];
    sort(a.begin(),a.end());
    reverse(a.begin(),a.end());
    cout<<(a[k-1]>=30?"Yes":"No")<<endl;
    return 0;
}