N,S,B = map(int, input().split())
H = list(map(int,input().split()))

for i in range(N-1):
    s = S
    while H[i]<H[i+1] and s>0:
        s -= 1
        H[i] += B
    if H[i]<H[i+1]:
        print("No")
        exit()
print("Yes")