#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<long long> VL;
typedef vector<VL> VVL;
typedef long long LL;
#define all(a) (a).begin(), (a).end()
#define Yes(n) cout << ((n) ? "Yes" : "No"  ) << endl
#define ALL(a)  (a).begin(),(a).end()
#define pb push_back

int main() {
  int n,ss,b;cin>>n>>ss>>b;
  int H[n];
  rep(i,n){cin>>H[i];}
  int g=H[0];
  LL s=LL(ss)*b;
  for(int i=1;i<n;i++){
    LL h=g+s;
    if(h>=H[i]){
      g=max(g,H[i]);
    }
    else{
      Yes(0);return 0;
    }
  }
  Yes(1);
}