import sys
N, S, B = map(int, sys.stdin.readline().rstrip().split())
H = list(map(int, sys.stdin.readline().rstrip().split()))

def kiriage(a, b):
    return (a+b-1)//b

for i in range(N - 1):
    stamina = S
    pos = H[i]
    nex = H[i + 1]
    diff = nex - pos

    if diff > 0: # 上昇が必要
        # stamina は diff / B だけ減る
        stamina -= kiriage(diff, B)

        if stamina < 0:
            exit(print('No'))

    else: # 不要
        pass

print('Yes')