import heapq 
from heapq import heappop,heappush,heapify
from sys import stdin, setrecursionlimit
input = stdin.readline
readline = stdin.readline

from collections import deque
d=deque()

#T=int(input())
N,S,B=map(int,input().split())
H=list(map(int, input().split()))
ans='Yes'
for i in range(1,N):
  H[i]=max(H[i],H[i-1])
  
for i in range(1,N):
  if H[i]-H[i-1]>S*B:
    ans='No'
print(ans)