import sys
import math
from itertools import product, permutations, combinations, accumulate
from heapq import heapify, heappush, heappop
from collections import deque, defaultdict, Counter
from bisect import bisect, bisect_left, bisect_right
from copy import copy, deepcopy
#from sortedcontainers import SortedSet, SortedList, SortedDict

sys.setrecursionlimit(10**7)
INF = float('inf')
LINF = 1 << 60
MOD = 10**9+7

def mii():
    return map(int, sys.stdin.readline().split())


N, S, B = mii()
H = list(mii())

ans = True

for i in range(N-1):
    if H[i+1] - H[i] > S*B:
        ans = False
        break

if ans:
    print("Yes")
else:
    print("No")